According to Agence France-Presse, Syrian state media reported Tuesday that rebel forces had launched a rocket attack on a hospital in a government-held neighborhood of Aleppo, Syria’s second city, leaving at least three dead and 17 others wounded.

Civil defense groups in Syria have accused Bashar al-Assad of using chlorine gas in at least 35 attacks on civilians since mid-March, the Guardian reports. “Whenever the regime loses an area or a city it arbitrarily takes revenge on civilians,” said White Helmets’ leader Raed Saleh. “It is targeting civilians.”