A Syrian boy receives treatment at a local hospital following a suspected chlorine gas attack in Idlib on April 27, 2015.
U.S. is 'certain' Syria used chlorine gas in attacks
02:21 - Source: CNN
Washington CNN  — 

Secretary of State John Kerry on Tuesday said he was “absolutely certain” that the Syrian government had attacked its own people with chlorine.

Asked by reporters about his confidence that Syrian President Bashar al-Assad had used chlorine gas to orchestrate a chemical attack, Kerry said he was “absolutely certain” it had occurred.

“We are certain that the preponderance of those attacks have been carried out by the regime, and we’re putting together a portfolio of that data that supports that even as we speak now,” Kerry said.

Obama himself has been cautious to accuse Assad outright of using chlorine in a chemical weapons attack, saying at a news conference last month that while chlorine has “historically” not been considered a chemical weapon, investigators were still working to learn how it has been used in Syria.

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Assad was largely stripped of the majority of his chemical weapons in 2013 after the U.S. threatened an attack due to their use but ultimately participated in a multinational deal under which the weapons were removed. Today Assad claims that the country’s chlorine gas is not being used for military purposes. The dead Syrians, Assad has said, are the result of the country’s cascading civil war.

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Kerry didn’t rule out the idea that some of the Syrians may have been killed due to the conflict, but he noted that “the opposition isn’t flying airlines or helicopters.”

Former Texas Gov. Rick Perry, one of a dozen Republican presidential hopefuls looking to succeed Obama, used Kerry’s comments Tuesday to criticize the president for being consistently weak whenever Assad engaged in chemical warfare.

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“President Obama is left to argue chlorine gas attacks on the Syrian people are not chemical warfare,” Perry said in a statement. “There is a great price to be paid when America does not lead, and innocent Syrian civilians are paying that price today.”