Civilian journalists confirmed by the AP reported Wednesday morning that Syrian President Bashar al-Assad’s army forces unleashed chemical weapons on rebel-controlled civilian areas of eastern and western Damascus.

Shortly afterward, news outlets published photos and videos of lines of corpses bearing no visible wounds. An exact death toll is still unknown. While British NGO Syrian Observatory for Human Rights estimates the attack claimed 40 casualties, Free Syrian Army sources place the number much higher at around 1,300 deaths.

Israel’s Prime Minister Benjamin Netanyahu commented, “This act adds to the roster of crimes committed by the Syrian regime, with the aid of Iran and Hezbollah, against the Syrian people.”

Reuters reported Thursday morning that additional shells launched by Assad’s forces bombarded the civilian neighborhoods along the eastern edge of Damascus.

Last year, United States President Barack Obama delineated Assad’s use of chemical weapons as a “red line” which would trigger U.S. intervention. While Syria-based United Nations inspectors have not yet investigated the alleged attack, the UN has called for an immediate inquiry into yesterday’s events.

In the past two years, more than 100,000 people have been killed in the Syrian Civil war.