Horrifying aftermath of Syria's chemical attack seen in graphic footage

One day after what the New York Times describes as "one of the worst chemical bombings in Syria," graphic images show the horrifying aftermath of the deadly gas attack.

An opposition-run Health Department at the rebel-held attack site in Idlib Province said 69 people -- including children -- had died in Tuesday's chemical attack, while some humanitarian groups are recounting a death toll up to 100.

While the attack is believed to have been a Syrian government-led strike, the Syrian military released a statement blaming insurgents, saying the army is accused of using toxic weapons "every time they fail to achieve the goals of their sponsors."

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According to the World Health Organization, victims of the gas attack showed symptoms mirroring those in reaction to a nerve agent. The U.S. has said the deaths were caused by sarin nerve gas dropped by Syrian aircraft, while the Syrian ally state of Russia has said the chemicals were likely leaked from a rebel stockpile of gas weapons.

"These types of weapons are banned by international law because they represent an intolerable barbarism," Peter Salama, Executive Director of the WHO Health Emergencies Programme, said in the WHO statement.

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The WHO said it was likely that some kind of chemical was used in the attack because victims had no apparent external injuries, but rather suffered from acute respiratory distress. Reports detail that victims choked, gasped and foamed at the mouth in reaction to the chemicals used in the attack.

Syrian use of chemical weapons was previously evidenced when hundreds died in Damascus in a 2013 sarin gas attack. Syrian President Bashar Al-Assad and his government have repeatedly denied responsibility for the attack.

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