Russia claims rebel chemical stockpile caused Syria gas deaths

The death toll from a suspected gas attack in Syria has risen to 72, as Russia has defended its ally in Damascus and said Syrian government air strikes hit a rebel chemical weapons depot.

UN secretary general Antonio Guterres said on Wednesday that the attack was a "war crime". 

Those killed on Tuesday in Khan Sheikhun included at least 20 children and 17 women, according to the Syrian Observatory for Human Rights, and the US government believes Sarin gas was used.

Syrian aviation made a strike on a large terrorist ammunition depot... There were workshops which produced chemical munitions

- Russian statement

Russia's defence ministry said on Wednesday that while Syrian aircraft had carried out a strike, the chemicals were part of a "terrorist" stockpile of "chemical munitions" that had been hit on the ground.

"Yesterday, from 11.30am to 12.30pm local time, Syrian aviation made a strike on a large terrorist ammunition depot and a concentration of military hardware in the eastern outskirts of Khan Sheikhun," ministry spokesman Igor Konoshenkov said in a statement on YouTube.

"On the territory of the depot there were workshops which produced chemical munitions."

A US government source said the chemical attack was "almost certainly" carried out by forces loyal to Syrian President Bashar al-Assad. The attack took place at about 6.30am local time, according to local statements to MEE - many hours before the Russian statement. 

Israeli security sources told Haaretz that the attack would have been approved at the highest levels of the Syrian government, to convey a message to rebels as it grew more confident of its stability after the takeover of Aleppo in December.

The Syrian Observatory for Human Rights said the chemical attack in the province of Idlib was carried out by warplanes believed to belong to the Syrian military.

Hasan Haj Ali, a commander of the Free Idlib Army rebel group, called the Russian statement a "lie".

"Everyone saw the plane while it was bombing with gas," he told Reuters from northwestern Syria.

"All the civilians in the area know that there are no military positions there, or places for the manufacture (of weapons). The various factions of the opposition are not capable of producing these substances."

Dan Kaszeta, a chemical weapons expert writing for the Bellingcat website, said the Russian narrative was "unlikely" for several reasons: Sarin is almost never stored in its active, deadly form and the effects of a direct hit by high explosives would not provide conditions to produce the agent.

"Dropping a bomb on the binary components (of Sarin) does not actually provide the correct mechanism for making the nerve agent," he said.

"It is an infantile argument. One of the precursors is isopropyl alcohol. It would go up in a ball of flame. A very large one. Which has not been in evidence."

The World Health Organisation on Wednesday repeated the reports from medics and doctors that victims of the attack showed symptoms consistent with reaction to a nerve agent.

"Some cases appear to show additional signs consistent with exposure to organophosphorus chemicals, a category of chemicals that includes nerve agents," it said, "The likelihood of exposure to a chemical attack is amplified by an apparent lack of external injuries."

The United States, Britain and France on Tuesday proposed a United Nations Security Council resolution condemning the attack, which they have blamed on Assad's forces. Diplomats said the resolution would probably be put to a vote on Wednesday.

All evidence points to Assad being behind the attack, said the British foreign secretary, Boris Johnson.

"All the evidence I have seen suggests this was the Assad regime... using illegal weapons on their own people," Johnson said as he arrived for a Syrian aid conference in Brussels.

The head of the health authority in rebel-held Idlib province said more than 50 people had been killed and 300 wounded in the attack.

The Union of Medical Care Organisations, a coalition of international aid agencies that funds hospitals in Syria, said the death toll was at least 100.

Speaking to MEE from Idlib on Tuesday, Ibrahim al-Seweid, 26, said he arrived at the attack site at about 11am, about three hours after the initial strike.

"I found bodies scattered all over the area. The local hospital wasn't prepared for the number of dead," he said.

"They hit a residential area, the vast majority of the casualties were civilian. And it was clear it was some sort of chemical attack - the way the victims looked, and there was foam on their faces.

"I could not stay for long, no one did - there were jets still flying in the sky and we feared another attack."

If confirmed, the chemical attack in Khan Sheikhun would be the deadliest in Syria since Sarin gas killed hundreds of civilians in Ghouta near Damascus in August 2013.