Washington (CNN)Secretary of State John Kerry on Thursday delivered a fiery response to reports that the Assad regime used chlorine gas as part of an attack earlier this week in the Syrian town of Sarmin.
Kerry condemns alleged Syrian chemical weapons use
In a written statement, Kerry said the United States is "deeply disturbed" by the as-yet-unverified reports. He called for a quick investigation into the allegations, though the State Department declined to spell out any specific consequences should they be proven.
"If true, this would be only the latest tragic example of the Assad regime's atrocities against the Syrian people, which the entire international community must condemn," Kerry said.
The attack, alleged to have taken place on Monday, was first reported by the Syrian Observatory for Human Rights.
Citing "civilian resources," the group claimed six civilians, including three children, had been killed in the attack and that dozens of others were injured.
CNN cannot independently confirm the accuracy of this report.
Last September, the Organization for the Prohibition of Chemical Weapons (OPCW) concluded, with "a high degree of confidence," that chlorine was used "systematically and repeatedly" in attacks in northern Syria, though the group did not specifically point fingers at the regime of Syrian President Bashar al-Assad.
The Syrian government agreed to turn over its declared chemical weapons stockpiles to the international community for destruction in 2013 as part of an agreement brokered by the U.S. and Russia and signed by the United Nations Security Council. The OPCW -- tasked with overseeing the process -- confirmed in June of last year that the final stockpile had been removed.
The Security Council resolution did not prohibit Syria from developing or storing chlorine because that chemical has non-violent, commercial uses.
However, the use of chlorine gas as a weapon is prohibited by the 1925 Chemical Weapons Convention, which Syria signed onto as part of the 2013 agreement.
This month, the Security Council passed a resolution condemning the use of chlorine gas in Syria and promising to take action if it were to be used again.
"The international community cannot turn a blind eye to such barbarism," Kerry said in his statement Thursday.
At the State Department's daily press briefing on Thursday, however, spokeswoman Jen Psaki gave no indication of how the U.S. might respond to the latest allegations of chemical weapons use.
"Because unfortunately we've had discussions about these issues in the past, the OPCW would be the governing body that would oversee and look into allegations, and then it would be a discussion with the international community," Psaki said, adding that the U.S. would consult with its partners but that "I don't have any predictions for what it will mean and what the consequences would be if the allegations are confirmed."
In his statement, Kerry underscored the need for a prompt investigation.
"The Assad regime's horrifying pattern of using chlorine as a chemical weapon against the Syrian people underscores the importance of investigating this allegation as quickly as possible," he said.
"As has been well documented," he continued, "the Assad regime continues to terrorize the people of Syria through indiscriminate airstrikes, barrel bombings, arbitrary detention, torture, sexual violence, murder, and starvation. The Assad regime must be held accountable for such atrocious behavior."
The Obama administration is supporting the moderate Syrian opposition fighting Assad in the ongoing Syrian civil war but has been reluctant to take direct action against the regime even as it fights the terror group ISIS in the northern part of the country.
While President Barack Obama had once labeled Syrian use of chemical weapons a "red line," he backed away from using military force to apply it in 2013 after running into opposition from Congress, and he has since made no signs of renewing that threat.
In an interview with CBS last week, Kerry said he would be willing to negotiate with the Assad regime to bring about a political solution to the conflict, though the State Department later clarified they see "no future" for Assad in Syria.