6 US troops killed by suicide bomber in Afghanistan

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6 Americans Killed in Suicide Attack

KABUL/WASHINGTON (Reuters) -- Six American troops were killed in Afghanistan on Monday when a suicide bomber on a motorbike struck their patrol near Bagram air base, a U.S. official said, in the latest high-profile attack claimed by Taliban insurgents.

Just days ago, the Pentagon warned of deteriorating security in Afghanistan in the second half of 2015 and a rise in the number of effective strikes by Taliban insurgents.

NATO's Resolute Support mission in Kabul said that the attack killed six Resolute Support troops and wounded three others but declined to provide the nationalities of casualties.

The police chief of Parwan province said three Afghan police had been wounded in the bombing, which was carried out just days after other suicide attacks on Kandahar air base in southern Afghanistan and on a Spanish embassy guesthouse in the Afghan capital, Kabul.

Bagram, around 40 km (25 miles) to the north of Kabul, is one of the main bases for the 9,800 U.S. troops left in Afghanistan after international troops ended combat operations last year.

District Governor Abdul Shukur Qudusi said the suicide bomber detonated his explosives near a joint U.S.-Afghan patrol.

The attack underlined the Taliban's ability to hit high-profile targets linked to the U.S.-backed government, which wants to reopen the peace process aimed at ending the 14-year-long insurgency.

On Monday, Taliban forces in Helmand closed in on the district of Sangin as they tightened their grip on the volatile southern province.

In a report to the U.S. Congress released last week, the Pentagon said casualties among Afghan national defense and security forces, or ANDSF, rose 27 percent from Jan. 1 to Nov. 15, compared with the same period last year.

Although the Pentagon praised Afghan forces for regaining territory and becoming increasingly capable of staging large-scale operations, it assessed their overall performance as "uneven and mixed."

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6 US troops killed by suicide bomber in Afghanistan
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 13, 2015, US army soldiers walk as a NATO helicopter flies overhead at coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 14, 2015, US army soldiers load ammunition into rifles during a military exercise inside coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
US soldiers part of NATO patrol during the final day of a month long anti-Taliban operation by the Afghan National Army (ANA) in various parts of eastern Nangarhar province, at an Afghan National Army base in Khogyani district on August 30, 2015. Afghan security forces launched a joint anti-militant operation in three districts, killing over 150 armed insurgents and wounding 112 others with 13 security personnel killed and three others were wounded in the past 30 days, Afghan National Army Commander Zaman Waziri said. AFP PHOTO / Noorullah Shirzada (Photo credit should read Noorullah Shirzada/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 14, 2015, Afghan National Army (ANA) soldiers are served lunch at a kitchen inside a base in the Khogyani districtin the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 14, 2015, US army soldiers fire during a military exercise inside coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, a US army soldier stands guard at an Afghan National Army (ANA) base in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, US army personnel keep watch at coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, US army soldiers play basketball at coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 14, 2015, a US army soldier and military dog keep watch as Afghan National Army (ANA) soldiers walk through coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, a US army soldier takes aim during a military exercise at coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 13, 2015, US army and Afghan National Army (ANA) soldiers walk as a NATO helicopter flies overhead at coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 13, 2015, US army soldiers play chess inside coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, a US army soldier poses for a photograph at coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, a US army soldier looks on with binoculars at Coalition forces Forward Operating Base (FOB) Connelly in Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, a US army soldier stands guard at an Afghan National Army (ANA) base in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, a US army soldier plays on a smartphone as he lies on a bed at coalition force Forward Operating Base (FOB) Connelly in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
TO GO WITH AFGHANISTAN-US-ARMY-CONFLICT-FOCUS BY GUILLAUME DECAMME In this photograph taken on August 12, 2015, US army soldiers walk past an Afghan National Army (ANA) base in the Khogyani district in the eastern province of Nangarhar. From his watchtower in insurgency-wracked eastern Afghanistan, US army Specialist Josh Whitten doesn't have much to say about his Afghan colleagues. 'They don't come up here anymore, because they used to mess around with our stuff. 'Welcome to Forward Operating Base Connelly, where US troops are providing training and tactical advice to the 201st Afghan army corps as they take on the Taliban on the battlefield. AFP PHOTO / Wakil Kohsar (Photo credit should read WAKIL KOHSAR/AFP/Getty Images)
A member of the U.S. Air Force stands guard, inside a C-130 Hercules aircraft, that belongs to the Afghan National Army, in Kandahar Air Field, Afghanistan, Tuesday, Aug. 18, 2015. Since the departure from Afghanistan last year of most international combat troops, Afghan security forces have been fighting the insurgency alone. Figures show that casualty rates are extremely high, reflecting an emboldened Taliban testing the commitment and strength of the Afghan military. (AP Photo/Massoud Hossaini)
U.S. military officers pay respect during a change of command ceremony in FOB Oqab, Kabul, Afghanistan, Monday, July 27, 2015. (AP Photo/Massoud Hossaini)
U.S. military vehicles stage at the site of a suicide attack that targeted a convoy of American troops in Jalalabad, east of Kabul, Aghanistan, Friday, April 10, 2015. An Afghan official says the bomb killed and wounded several civilians. The Taliban have claimed responsibility for the attack. (AP Photo)
U.S. Defense Secretary Chuck Hagel speaks to American troops during a visit in FOB Gamberi, Afghanistan, Sunday, Dec. 7, 2014. Hagel visited the Forward Operating Base to meet with Afghanistan military officials and visit with American troops stationed there. (AP Photo/Mark Wilson, Pool)
US military forces listen to U.S. Secretary of Defense Chuck Hagel speaking at Tactical Base Gamberi in eastern Afghanistan, Sunday, Dec. 7, 2014. Hagel was winding up a two day visit, his last to Afghanistan as secretary of defense. (AP Photo/Mark Wilson, Pool)
FILE- In this file photo taken Sept. 23, 2009, a column of U.S. Army mine-resistant armored vehicles (MRAPs) and Afghan National Army vehicles pass through a village during a joint patrol in the Jalrez Valley in Afghanistan's Wardak Province. As the United States military packs up to leave Afghanistan, ending 13 years of war, it is looking to sell or dispose of billions of dollars in military hardware, including its sophisticated and highly specialized mine resistant vehicles, but finding a buyer is complicated in a region where relations between neighboring countries are mired in suspicion and outright hostility.(AP Photo/Maya Alleruzzo, file)
US soldiers and service members with the NATO- led International Security Assistance Force (ISAF) attend a religious ceremony on Christmas Eve at Bagram military base in Kabul, Afghanistan, Tuesday Dec. 24, 2013. The commander of NATO forces in eastern Afghanistan spent Christmas Eve visiting U.S. troops at bases across the mountainous region to bring them holiday greetings and gifts for a few lucky soldiers. (AP Photo/Rahmat Gul)
In this Monday, Dec. 9, 2013 photo provided by the U.S. Department of Defense, Joint Chiefs Chairman Gen. Martin E. Dempsey, center, arrives at Kandahar Regional Medical Hospital to visit medical staff and patients in Kandahar province, Afghanistan. America's top military officer said Tuesday the U.S. does not intend to renegotiate a security deal with Afghanistan and that a full withdrawal of its forces from the country at the end of 2014 could reverse gains made by Afghan troops in their war against the Taliban. (AP Photo/D. Myles Cullen, DOD)
In this March 22, 2013, photo, U.S. Marine Major Christopher Bourbeau, deputy commander at the 1st Brigade, 215th Corps Afghanistan National Army Advisor Team, at Camp Garmser, Helmand province, in southern Afghanistan, staging a pop quiz on how to tie tourniquets for the Afghan army troops he advises. The Afghan soldier tied the tourniquet in just over 30 seconds. U.S. commanders trying to hand off war-fighting responsibility by the end of 2014 are encouraged by the uneven yet steady progress of fledgling Afghan security forces. (AP Photo/Kim Dozier)
A Chinock window gunner guards, near U.S. Secretary of Defense Chuck Hagel, on a helicopter over Kabul, Afghanistan, Sunday, Dec. 8, 2013. Hagel spoke with troops and thanked them for being deployed for the holidays. (AP Photo/Mark Wilson, Pool)
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