Obama calls IS beheadings 'pure evil'

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U.S. Aid Worker Murder 'Pure Evil'

BEIRUT (AP) -- The Islamic State group has beheaded Peter Kassig, releasing a video Sunday showing a masked militant standing over the severed head of a man it said was the former U.S. Army Ranger-turned-aid worker, who was seized while delivering relief supplies in Syria last year.

President Barack Obama confirmed Kassig's slaying after a U.S. review of the video, which also showed the mass beheadings of a dozen Syrian soldiers.

The 26-year-old Kassig, who founded an aid group to help Syrians caught in their country's brutal civil war, "was taken from us in an act of pure evil by a terrorist group that the world rightly associates with inhumanity," Obama said in a statement.

He denounced the extremist group, which he said "revels in the slaughter of innocents, including Muslims, and is bent only on sowing death and destruction."

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Obama calls IS beheadings 'pure evil'
FILE - In this undated file photo provided by his family, Peter Kassig stands in front of a truck filled with supplies for Syrian refugees. The Indianapolis, Indiana, aid worker being held by the Islamic State group told family and teachers that heâd found his calling in 2012 when he decided to stay in the Middle East instead of returning to college, according to an email released Tuesday, Oct. 14, 2014 by his family. (AP Photo/Courtesy Kassig Family, File)
French President Francois Hollande raises his hands as he speaks at the National Gallery of Australia in Canberra, Australia, Wednesday Nov. 19, 2014. (AP Photo/Cole Bennetts, Pool)
This still image taken from an undated video published on the Internet by the Islamic State group militants and made available, Sunday, Nov. 16, 2014 shows a militant that the French government say is Frenchman Maxime Hauchard . Interior Minister Bernard Cazeneuve said there is a "strong presumption" that Maxime Hauchard is among the group of Islamic extremist fighters in the video released over the weekend. He urged young people in France to "open your eyes to the terrible reality" of the militant group. The high-definition video shows the beheadings of about a dozen men identified as Syrian military officers and pilots, all dressed in blue jumpsuits. The Associated Press could not independently verify the footage, though it appeared on websites used in the past by the Islamic State group, which now controls a third of Syria and Iraq. (AP Photo)
WASHINGTON, DC - NOVEMBER 16: U.S. President Barack Obama returns to the White House on Marine One on November 16, 2014 in Washington, DC. Obama is returning from Brisbane, Australia where he attended the G20 Leader's Summit. (Photo by Dennis Brack-Pool/Getty Images)
"We are heartbroken to learn that our son has lost his life as a result of his love for the Syrian people." #Kassig http://t.co/5TbmxSs9Fk
Ed & Paula Kassig: "We are incredibly proud of our son for living his life according to his humanitarian calling." http://t.co/Iqm0lCBOY8
This still image from an undated video released by Islamic State militants on Tuesday, Aug. 19, 2014, purports to show journalist Steven Sotloff being held by the militant group. The Islamic State group has threatened to kill Sotloff if the United States doesn't stop its strikes against them in Iraq. Sotloff's mother, Shirley Sotloff, pleaded for his release Wednesday, Aug. 27, 2014, in a video message aimed directly at his captors that aired on the Al-Arabiya television network. (AP Photo)
MISRATA, LIBYA - JUNE 02: In this handout image made available by the photographer American journalist Steven Sotloff (Center with black helmet) talks to Libyan rebels on the Al Dafniya front line, 25 km west of Misrata on June 02, 2011 in Misrata, Libya. Sotloff was kidnapped in August 2013 near Aleppo, Syria and was recently shown on a jihadist video in which fellow US journalist James Foley was executed. In the video the militant form the Islamic State (IS) threatens to kill Sotloff next if the US continues its aerial campaign against the insurgency. (Photo by Etienne de Malglaive via Getty Images)
Daily News front page Agusut 20, 2014, SAVAGES - ISIS monster behead U.S. journalist, taunt Obama over air strikes in Iraq - James Foley. (Photo By: /NY Daily News via Getty Images)
British hostage James Cantlie shown in "Lend Me Your Ears: Episode 2." (Clarion Project)
FILE - This undated file image posted on a militant website on Tuesday, Jan. 14, 2014, which has been verified and is consistent with other AP reporting, shows fighters from the al-Qaida linked Islamic State of Iraq and the Levant (ISIL) marching in Raqqa, Syria. Moderate Syrian rebels are buckling under the onslaught of the radical al-Qaida breakaway group that has swept over large parts of Iraq and Syria. Some rebels are giving up the fight, crippled by lack of weapons and frustrated with the power of the Islamic State of Iraq and the Levant. Other, more hard-line Syrian fighters are bending to the winds and joining the radicals. (AP Photo/Militant Website, File)
In this undated photo provided by the Kassig family, Peter Kassig, is shown with his maternal grandparents. His grandfather, a co-founder of Christians for Peace and Justice in the Middle East, was an advocate for Palestinians in their struggle for a homeland. The Islamic State group released a graphic video on Sunday, Nov. 16, 2014, in which a black-clad militant claimed to have beheaded U.S. aid worker Peter Kassig, who was providing medical aid to Syrians fleeing the civil war when he was captured inside Syria on Oct. 1, 2013. His friends say he converted to Islam in captivity and took the first name Abdul-Rahman. (AP Photo/Courtesy Kassig Family)
FILE - In this August 2013 file photo provided by the Kassig Family, Peter Kissig, who friends and family say changed his name to Abdul-Rahman Kassig, right, works as a medic to help a wounded man near Deir Ezzor, Syria. A new graphic video purportedly produced by Islamic State militants in Syria released Sunday Nov. 16, 2014 claims U.S. aid worker Kassig was beheaded. (AP Photo/Courtesy Kassig Family, File)
Syrian refugees, doctor Ahmed Obaid, left, Firas Mousa, center, and Safwan Khatib, right, all colleagues of American aid worker Peter Kassig, 26, who converted to Islam while in captivity and changed his name to Abdul-Rahman Kassig, hold up signs during a press conference in the northern port city of Tripoli, Lebanon, Saturday, Nov. 8, 2014. Several Syrian friends of Kassig who is held by the Islamic State group and threatened of being beheaded have called for his release saying he converted to Islam and was helping Syrians. (AP Photo/Bilal Hussein)
Syrian refugee Amjad Moghrabi stands in front of a photograph of his colleague, American aid worker Peter Kassig, 26, who converted to Islam while in captivity and changed his name to Abdul-Rahman Kassig, during an interview with The Associated Press in the northern port city of Tripoli, Lebanon, Saturday, Nov. 8, 2014. Kassig was helping victims of the Syrian civil war when he was captured in Syria last year and threatened with beheading by the Islamic State group. Arabic reads, "Justice for Abdul-Rahman." (AP Photo/Bilal Hussein)
Cantlie rails against Obama's "simplistic" speeches and "under-construction" army. (Clarion Project)
ISIS also went to great efforts to cite American media both quoting the president and showing criticism of his strategies, in this case using a CNN article. (Clarion Project)
FILE - This undated file image posted on a militant website on Tuesday, Jan. 14, 2014, which has been verified and is consistent with other AP reporting, shows fighters from the al-Qaida linked Islamic State of Iraq and the Levant (ISIL) marching in Raqqa, Syria. Moderate Syrian rebels are buckling under the onslaught of the radical al-Qaida breakaway group that has swept over large parts of Iraq and Syria. Some rebels are giving up the fight, crippled by lack of weapons and frustrated with the power of the Islamic State of Iraq and the Levant. Other, more hard-line Syrian fighters are bending to the winds and joining the radicals. (AP Photo/Militant Website, File)
FILE- This undated image posted by the Raqqa Media Center, a Syrian opposition group, on Monday, June 30, 2014, which has been verified and is consistent with other AP reporting, shows fighters from the al-Qaida linked Islamic State group during a parade in Raqqa, Syria. The Gulf nation of Qatar is hitting back at suggestions that it supports the Islamic State extremist group, saying that “determined, collective action” is needed to end sectarian violence gripping Iraq and Syria. Qatari Foreign Minister Khalid bin Mohammed al-Attiyah unequivocally denied funding the extremist group. (AP Photo/Raqqa Media Center- File)
This undated image posted by the Raqqa Media Center, a Syrian opposition group, on Monday, June 30, 2014, which has been verified and is consistent with other AP reporting, shows fighters from the al-Qaida linked Islamic State of Iraq and the Levant (ISIL) during a parade with a missile in Raqqa, Syria. Militants from an al-Qaida splinter group held a military parade in their stronghold in northeastern Syria, displaying U.S.-made Humvees, heavy machine guns, and missiles captured from the Iraqi army for the first time since taking over large parts of the Iraq-Syria border. (AP Photo/Raqqa Media Center)
US President Barack Obama speaks during a primetime address to the nation from the Cross Hall of the White House in Washington, DC, September 10, 2014. AFP PHOTO / POOL / Saul LOEB (Photo credit should read SAUL LOEB/AFP/Getty Images)
U.S. President Barack Obama speaks during a televised address at the White House in Washington, D.C., U.S., on Wednesday, Sept. 10, 2014. Obama pledged a relentless campaign to destroy Islamic State extremists in Iraq and Syria, with Middle Eastern allies such as Saudi Arabia and Jordan playing crucial supporting roles. Photographer: Saul Loeb/Pool via Bloomberg
U.S. President Barack Obama leaves after speaking during a televised address at the White House in Washington, D.C., U.S., on Wednesday, Sept. 10, 2014. Obama pledged a relentless campaign to destroy Islamic State extremists in Iraq and Syria, with Middle Eastern allies such as Saudi Arabia and Jordan playing crucial supporting roles. Photographer: Saul Loeb/Pool via Bloomberg
FILE - In this Sept. 5, 2014, file photo U.S. President Barack Obama looks around during a flypast at the NATO summit in Newport, Wales. Obama will begin this week to lay out a strategy to defeat Islamic State militants in the Middle East, starting with a White House meeting with bipartisan congressional leaders on Tuesday, Sept. 9, 2014 and a speech on Wednesday, the eve of the 13th anniversary of the deadliest terrorist attack on U.S. soil. (AP Photo/Jon Super, File)
NEWPORT, WALES - SEPTEMBER 04: US President Barack Obama (L) meets with British Prime Minister David Cameron at the NATO Summit on September 4, 2014 in Newport, Wales. Leaders and senior ministers from around 60 countries are meeting at what has been billed as the most important Nato summit since the end of the cold war with the situation in Ukraine and the threat of ISIS likely to be top of the agenda. (Photo by Peter Macdiarmid - WPA Pool /Getty Images)
This Thursday, Sept. 4, 2014, the mother of a missing Lebanese soldier who was kidnapped by Islamic State militants, shouts slogans against the Lebanese cabinet during a demonstration to demand action to secure the captives' release, in front the Lebanese government building, in downtown Beirut, Lebanon. The mother of Lebanese soldier Abbas Medlej, held captive by the militant Islamic State group says that photographs posted online purporting to show his beheading appear real, on Saturday, Sept. 6, 2014. Militants, including from the Islamic State extremist group, seized around 30 soldiers and policemen after overrunning a Lebanese border town in early August. (AP Photo/Hussein Malla, File)
This Thursday, Sept. 4, 2014, a family of a missing Lebanese soldier who was kidnapped by Islamic State militants, sits on the ground as they block a street during a demonstration to demand action to secure the captives' release, in front the Lebanese government building, in downtown Beirut, Lebanon. The mother of Lebanese soldier Abbas Medlej, held captive by the militant Islamic State group says that photographs posted online purporting to show his beheading appear real, on Saturday, Sept. 6, 2014. Militants, including from the Islamic State extremist group, seized around 30 soldiers and policemen after overrunning a Lebanese border town in early August. (AP Photo/Hussein Malla, File)
Families of missing soldiers who were kidnapped by Islamic State militants and the Al-Nusra front, sit on the ground street as they hold Arabic banners that read: "you should be ashamed of the blood of the hero martyr Ali Sayid (the beheaded Lebanese soldier)," left, "Hey politicians the blood of our sons is in your hands," center, and "If your children were among those kidnapped ... what would you have done?" right, during a demonstration to demand action to secure the captives' release, in front the Lebanese government building, in downtown Beirut, Lebanon, on Thursday Sept. 4, 2014. Lebanon's government is forming a crisis committee to handle the case of some two dozen members of the security forces held captive by Syrian militants amid escalating criticism over its response to the hostage affair. Militants, including from the Islamic State extremist group, seized around 30 soldiers and policemen after overrunning a Lebanese border town in early August. (AP Photo/Hussein Malla)
Students and supporters take part in a candle light vigil at the University of Central Florida, Wednesday, Sept. 3, 2014, in Orlando, Fla., to honor Steven Sotloff, the second American journalist to be beheaded by the Islamic State group in two weeks. Sotloff attended University of Central Florida between 2002 and 2004. (AP Photo/John Raoux)
U.S. President Barack Obama pauses as he speaks about the killing of journalist James Foley in Syria during a statement in Edgartown, Mass., Wednesday, Aug. 20, 2014. The president said the U.S. will continue to confront Islamic State extremists despite Foley's brutal murder. Obama said he spoke Wednesday with Foley's family and offered condolences. (AP Photo/Jacquelyn Martin)
Diane and John Foley talk to reporters after speaking with U.S. President Barack Obama Wednesday, Aug. 20, 2014 outside their home in Rochester, N.H. Their son, James Foley was abducted in November 2012 while covering the Syrian conflict. Islamic militants posted a video showing his murder on Tuesday and said they killed him because the U.S. had launched airstrikes in northern Iraq. (AP Photo/Jim Cole)
NEWPORT, WALES - SEPTEMBER 04: (L-R) British Prime Minister David Cameron, NATO Secretary General Anders Fogh Rasmussen and US President Barack Obama talk as they arrive at the NATO Summit on September 4, 2014 in Newport, Wales. Leaders and senior ministers from around 60 countries are gathering for the two day meeting where Ukraine and the ISIS hostages are likely to be discussed. (Photo by Chris Ratcliffe - Pool/Getty Images)
NEWPORT, WALES - SEPTEMBER 04: British Prime Minister David Cameron gestures to US President Barack Obama as they arrive at the NATO Summit on September 4, 2014 in Newport, Wales. Leaders and senior ministers from around 60 countries are gathering for the two day meeting where Ukraine and the ISIS hostages are likely to be discussed. (Photo by Chris Ratcliffe - Pool/Getty Images)
Julian Lang, left, and Andrea Henriquez join students and supporters in a candle light vigil at the University of Central Florida, Wednesday, Sept. 3, 2014, in Orlando, Fla., to honor Steven Sotloff, the second American journalist to be beheaded by the Islamic State group in two weeks. Sotloff attended University of Central Florida between 2002 and 2004. (AP Photo/John Raoux)
This undated image posted on Wednesday, Aug. 27, 2014 by the Raqqa Media Center of the Islamic State group, a Syrian opposition group, which has been verified and is consistent with other AP reporting, shows a fighter of the Islamic State group waving their flag from inside a captured government fighter jet following the battle for the Tabqa air base, in Raqqa, Syria on Sunday. A U.N. commission on Wednesday accused the extremist Islamic State organization of committing crimes against humanity with attacks on civilians, as pictures emerged of the extremists' bloody takeover of a Syrian military air base that added to the international organization’s claims. (AP Photo/ Raqqa Media Center of the Islamic State group)
This undated image posted on Wednesday, Aug. 27, 2014 by the Raqqa Media Center of the Islamic State group, a Syrian opposition group, which has been verified and is consistent with other AP reporting, shows fighters of the Islamic State waving the group's flag from a damaged display of a government fighter jet following the battle for the Tabqa air base, in Raqqa, Syria. A U.N. commission on Wednesday accused the extremist Islamic State organization of committing crimes against humanity with attacks on civilians, as pictures emerged of the extremists' bloody takeover of a Syrian military air base that added to the international organization’s claims. (AP Photo/ Raqqa Media Center of the Islamic State group)
This undated image posted Wednesday, Aug. 27, 2014 by the Raqqa Media Center of the Islamic State group, a Syrian opposition group, which has been verified and is consistent with other AP reporting, shows Abu Moussa al-Ansari, a fighter from the Islamic State group, who they say was killed in the battle for the Tabqa air base, in Raqqa, Syria. A U.N. commission on Wednesday accused the extremist Islamic State organization of committing crimes against humanity with attacks on civilians, as pictures emerged of the extremists' bloody takeover of a Syrian military air base that added to the international organization’s claims. (AP Photo/ Raqqa Media Center of the Islamic State group)
FILE - This undated file image posted on a militant website on Tuesday, Jan. 14, 2014 shows fighters from the al-Qaida linked Islamic State of Iraq and the Levant (ISIL) patrolling in Raqqa, Syria. The ISIL led by Abu Bakr al-Baghdadi, who is believed to have been operating from inside Syria in recent months, is the main driver of destabilizing violence in Iraq and until recently was the main al-Qaida affiliate there. Al-Qaida’s general command formally disavowed the group this week, saying it "is not responsible for its actions." (AP Photo/militant website, File)
In this image taken from video obtained from the Shaam News Network, which has been authenticated based on its contents and other AP reporting, a government soldier bombs neighborhoods near the al-Maza airport, in Damascus countryside, Syria, on Monday, Nov. 4, 2013. (AP Photo/Shaam News Network via AP video)
Druze men stand in the Israeli-annexed Golan Heights as they look at smoke rising in the distance caused by fighting between forces loyal to Syrian President Bashar Assad and rebels over the control of the Quneitra border crossing, on August 27, 2014. Syrian rebels, including Al-Qaeda's affiliate Al-Nusra Front, seized control of the Syrian crossing with the Israeli-occupied Golan Heights today, the Britain-based Syrian Observatory for Human Rights said. AFP PHOTO / JACK GUEZ (Photo credit should read JACK GUEZ/AFP/Getty Images)
Members of United Nations Disengagement Observer Force Zone (UNDOF) use binoculars to watch smoke rising in the distance caused by fighting between forces loyal to Syrian President Bashar Assad and rebels over the control of the Quneitra border crossing, on August 27, 2014. Syrian rebels, including Al-Qaeda's affiliate Al-Nusra Front, seized control of the Syrian crossing with the Israeli-occupied Golan Heights today, the Britain-based Syrian Observatory for Human Rights said. AFP PHOTO / JACK GUEZ (Photo credit should read JACK GUEZ/AFP/Getty Images)
This undated image posted Wednesday, Aug. 27, 2014 by the Raqqa Media Center of the Islamic State group, a Syrian opposition group, which has been verified and is consistent with other AP reporting, shows fighters from the Islamic State group that captured the Tabqa air base from the Syrian government on Sunday, firing a captured tank, in Raqqa, Syria. A U.N. commission on Wednesday accused the extremist Islamic State organization of committing crimes against humanity with attacks on civilians, as pictures emerged of the extremists' bloody takeover of a Syrian military air base that added to the international organization’s claims. (AP Photo/ Raqqa Media Center of the Islamic State group)
A rebel fightercarries homemade mortar rounds on September 3, 2013 in the northern Syrian city of Raqqa. UN leader Ban Ki-moon said on September 3, 2013 that a military strike on Syria over the use of chemical weapons could worsen the country's conflict. AFP PHOTO / MEZAR MATAR (Photo credit should read MEZAR MATAR/AFP/Getty Images)
A Muslim woman releases a dove as a symbol of peace during a rally against the Islamic State group, in Jakarta, Indonesia, Friday, Sept. 5, 2014. The banner reads: "ISIS is not Islam's voice. Stop Killing journalist." (AP Photo/Tatan Syuflana)
Displaced Iraqis from the Yazidi community cross the Iraqi-Syrian border along the Fishkhabur bridge over Tigris River at the Fishkhabur crossing, in northern Iraq, on August 11, 2014. At least 20,000 civilians, many of whom are from the Yazidi community, who had been besieged by jihadists on a mountain in northern Iraq have safely escaped to Syria and been escorted by Kurdish forces back into Iraq, officials said. The breakthrough coincided with US air raids on Islamic State fighters in the Sinjar area of northwestern Iraq on August 9, and Kurdish forces from Iraq, Syria and Turkey working together to break the siege of Mount Sinjar and rescue the displaced. AFP PHOTO/AHMAD AL-RUBAYE (Photo credit should read AHMAD AL-RUBAYE/AFP/Getty Images)
Peshmerga forces hand out water bottles and show the way to displaced Iraqi families from the Yazidi community as they cross the Iraqi-Syrian border at the Fishkhabur crossing, in northern Iraq, on August 11, 2014. At least 20,000 civilians, most of whom are from the Yazidi community, who had been besieged by jihadists on a mountain in northern Iraq have safely escaped to Syria and been escorted by Kurdish forces back into Iraq, officials said. The breakthrough coincided with US air raids on Islamic State fighters in the Sinjar area of northwestern Iraq on August 9, and Kurdish forces from Iraq, Syria and Turkey working together to break the siege of Mount Sinjar and rescue the displaced. AFP PHOTO/AHMAD AL-RUBAYE (Photo credit should read AHMAD AL-RUBAYE/AFP/Getty Images)
Kurdish Peshmerga fighters hold a position on the front line in the Gwer district, 40 kilometres south of Arbil, the capital of the Kurdish autonomous region in northern Iraq, on September 18, 2014. France said that it will follow the United States in launching air strikes against the Islamic State group in Iraq, as the jihadists posted their latest video of a Western hostage. AFP PHOTO / SAFIN HAMED (Photo credit should read SAFIN HAMED/AFP/Getty Images)
Kurdish Peshmerga fighters hold a position on the front line in the Gwer district, 40 kilometres south of Arbil, the capital of the Kurdish autonomous region in northern Iraq, on September 18, 2014. France said that it will follow the United States in launching air strikes against the Islamic State group in Iraq, as the jihadists posted their latest video of a Western hostage. AFP PHOTO / SAFIN HAMED (Photo credit should read SAFIN HAMED/AFP/Getty Images)
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The slain hostage's parents, Ed and Paula Kassig, said they were "heartbroken" by their son's killing, but "incredibly proud" of his humanitarian work.

Kassig "lost his life as a result of his love for the Syrian people and his desire to ease their suffering," the parents said in a statement from Indianapolis, where a vigil was held Sunday for the slain American. His parents attended the vigil.

With Kassig's death, the Islamic State group has killed five Westerners it was holding. American journalists James Foley and Steven Sotloff were beheaded, as were British aid workers David Haines and Alan Henning.

Unlike previous videos of slain Western hostages, the footage released Sunday did not show the decapitation of Kassig or the moments leading up to his death.

"This is Peter Edward Kassig, a U.S. citizen ... who fought against the Muslims in Iraq," said the black-clad militant, who spoke with a British accent that was distorted in the video, apparently to disguise his identity. Previous videos featured a militant with a British accent that the FBI says it has identified, though it hasn't named him publicly.

The footage released Sunday identifies the militants' location as Dabiq, a town in northern Syria that the Islamic State group uses as the title of its English-language propaganda magazine and where they believe an apocalyptic battle between Muslims and their enemies will occur.

The high-definition video also showed the beheadings of about a dozen men identified as Syrian military officers and pilots, all dressed in blue jumpsuits. The black-clad militant warns that U.S. soldiers will meet a similar fate.

"We say to you, Obama: You claim to have withdrawn from Iraq four years ago," the militant said. "Here you are: You have not withdrawn. Rather, you hid some of your forces behind your proxies." A U.S.-led coalition is targeting the Islamic State group in airstrikes, supporting Western-backed Syrian rebels, Kurdish fighters and the Iraqi military.

Kassig, who served in the U.S. Army's 75th Ranger Regiment, a special operations unit, deployed to Iraq in 2007. After being medically discharged, he returned to the Middle East in 2012 and formed a relief group, Special Emergency Response and Assistance, to aid Syrian refugees.

A certified EMT, Kassig had delivered food and medical supplies and provided trauma care to wounded Syrians before being captured in eastern Syria on Oct. 1, 2013. Friends say he converted to Islam in captivity and took the first name Abdul-Rahman.

In a statement issued as he flew back to Washington from the Asia-Pacific region, Obama said Kassig "was a humanitarian who worked to save the lives of Syrians injured and dispossessed" by war. The president offered prayers and condolences to Kassig's family.

"We cannot begin to imagine their anguish at this painful time," he said.

Burhan Agha, a Syrian who worked with Kassig in Lebanon, wept when recounting his friend's humanitarian work.

"If I could apologize to each American, one by one, I would, because Peter died in Syria, while he was helping the Syrian people," Agha told The Associated Press by telephone from Switzerland, where he is seeking asylum. "Those who killed him claimed to have done it in the name of Islam. I am a Muslim and am from Syria. ... (His killers) are not Muslims."

British Prime Minister David Cameron said he was "horrified by the cold-blooded murder," saying that the Islamic State group had "again shown their depravity."

In previous videos showing the beheadings of the two American journalists and two British aid workers, the hostages were shown kneeling in orange jumpsuits as they were forced to make speeches before their killer lifted a knife to their throats.

The latest video did not show Kassig being beheaded. And unlike previous videos, it did not show other Western captives or directly threaten to behead anyone else. It also had lingering close-ups on some militants' exposed faces, a few of whom appeared to be foreigners.

The video appeared on websites used in the past by the Islamic State group, which now controls a third of Syria and Iraq.

The terror group still holds other captives, including British photojournalist John Cantlie, who has appeared in several videos delivering statements for the IS, likely under duress, and a 26-year-old American woman captured last year in Syria while working for aid groups. U.S. officials have asked that the woman not be identified out of fears for her safety.

The video appeared to be part of continuous efforts to strike at the U.S., which is leading an aerial campaign against the group that began in August in Iraq and spread to Syria the following month.

The video came two days after a recording by the group's leader, Abu Bakr al-Baghdadi, was uploaded to the Internet. The militant leader warned that the U.S.-led coalition's campaign had failed and it would eventually have to send ground troops into battle.

The group has declared a self-styled Islamic caliphate in areas under its control, which it governs according to its violent interpretation of Shariah law, including massacring rebellious tribes and selling women and children of religious minorities into slavery.

The group's militants have also beheaded and shot dead hundreds of captives, mostly Syrian and Iraqi soldiers, during its sweep across the two countries, and has celebrated its mass killings in extremely graphic videos.

The Islamic State group has its roots in al-Qaida's Iraqi affiliate but was expelled from the global terror network over its brutal tactics and refusal to obey orders to confine its activities to Iraq. It became even more extreme amid the bloody civil war in neighboring Syria and grew strong enough to launch a lightning offensive across Iraq.

Syria's war began as an uprising against President Bashar Assad. Activists say that conflict has killed more than 200,000 people.

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