There has been another reported chemical weapon attack in Syria. More than 100 people were hospitalized after barrel bombs containing chlorine were dropped in the city of Aleppo. CNN reports:

The US-based Syrian American Medical Society, which supports one of three hospitals in Aleppo where the victims were taken, said one person was killed by the barrel bombs dropped during the alleged chemical attack on the Sukkari neighborhood Tuesday.

At least 37 children and ten women were among those hospitalized, the Aleppo Free Doctors Committee said…

The UK-based Syrian Observatory for Human Rights also reported the attack, saying that medical sources accused regime warplanes of pounding the Sukkari neighborhood with barrel bombs “laden with poison gas.”

The area where the bombs were dropped is described by CNN as “rebel- held” meaning the attack likely came from the Assad regime.

President Obama warned in 2012 he might use military force against Syria if Assad crossed the “red line” of using chemical weapons in the country’s civil war. When it became clear Assad had done so, Obama changed course and instead reached an agreement with Syria that required it to turn over all of its chemical weapons for destruction. CNN notes that chlorine was not part of that deal because it has other, legitimate uses as an industrial chemical.

Last month a UN investigation concluded Assad’s regime had used chemical weapons at least twice since reaching an agreement to turn over all chemical weapons in 2013. Both of those attacks were made with bombs containing chlorine.