The United States Department of Defense says they suspect Syrian President Bashar al-Assad used chemical weapons on a “small scale” in that country’s ongoing civil war.

US Defense Secretary Chuck Hagel made the claim Thursday while speaking in Abu Dhabi, United Arab Emirates, adding that the American intelligence community has determined “with varying degrees of confidence that the Syrian regime has used chemical weapons on a small scale in Syria, specifically the chemical agent sarin."

Hagel insisted that the use of chemical weapons by any army would violate international guidelines for armed conflicts, and said confirmation of these reports would be a “ game changer ” in terms of America’s role in the Syrian civil war.

"It violates every convention of warfare,” said Hagel, the Associated Press reports.

The White House informed Congress about the use of chemical weapons during a Thursday briefing, continues the AP. White House legislative director Miguel Rodriguez sent a letter to Senators John McCain (R-Arizona) and Carl Levin (D-Michigan) explaining that "because the president takes this issue so seriously, we have an obligation to fully investigate any and all evidence of chemical weapons use within Syria."

"Thus far, we believe that the Assad regime maintains custody of these weapons, and has demonstrated a willingness to escalate its horrific use of violence against the Syrian people," Foreign Policy quotes from the letter.

Moments after news of the letter were first reported, Sen. McCain walked out of a briefing in Washington with Secretary of State John Kerry and told reporters, "We just received a letter from the president in response to our question about whether Assad had used chemical weapons.”

Photo by Aleppo University Hospital

Kerry, reports the AP, said the Syrian regime launched two chemical weapons attacks during that Thursday morning meeting, which Foreign Policy says was attended by reportedly all US senators, as well as representatives for the office of the director of national intelligence and the Federal Bureau of Investigation.

Speaking to CNN shortly later, Sen. McCain said he’s not surprised by the latest intelligence report and has long assumed that Assad’s regime was engaged in chemical warfare. Of specific concern to him, however, was what could happen if the alleged warheads end up in the arsenals of others.

“I think they have control over them at the moment,” he said of the weapons, “but some of them are in heavily contested areas and could easily fall into the hands of jihadist extremists.”

“We need to have operational capability to secure these weapons,” added McCain.

S President Barack Obama said previously that the use of chemical weapons in Syria would be a "red line" that could trigger US reaction if crossed. On Thursday Rodriguez wrote on behalf of the administration that “physiological samples" has led the White House to reassess the claims that Assad has used chemical warfare. Christiane Amanpour, the chief international correspondent for CNN, said that sources have told her that physicians working with the Free Syrian Army obtained blood samples from chemical warfare victims and provided them to US intelligence along with soil samples collected from the earth. 

Photo by Aleppo University Hospital

Britain, France, Qatar and the Israel Defense Forces have also said in recent days that Israeli intelligence has led them to believe Assad has used chemical weapons.

Intelligence assessments on Syrian chemical weapons are “not enough,” Reuters quotes the White House, adding that “credit and corroborated facts” are needed.

Even one day earlier, Sec. Hagel himself had doubts about the rumored use of chemical weapons. Speaking in Cairo, Egypt on Wednesday, Hagel said that Israeli claims of Assad employing chemical warfare were “suspicious” and that “we have to be very careful here before we draw any conclusions based on real intelligence.”

“The use of chemical weapons in an environment like Syria is very difficult to confirm,” a senior US Defense official told the Los Angeles Times in response while speaking on condition of anonymity. “Given the stakes involved, low-confidence assessments by foreign governments cannot be the basis for US action.”

Photo by Aleppo University Hospital

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