The bomb exploded as people were leaving the evening prayers The explosion burned down at least six shops AZAZ, Syria: At least 19 people were killed Sunday in a car bomb near a bustling market and mosque in a rebel-held city in northwestern Syria, a war monitor said. Four children were among those killed in the explosion in Azaz, in the heart of a Turkish zone of influence in Aleppo province, said the Syrian Observatory for Human Rights. The attack also wounded more than 20 people, according to the Britain-based monitor. “Many people were leaving evening prayers when the explosion happened,” Observatory head Rami Abdul Rahman told AFP. Shoppers buying clothes and gifts ahead of the upcoming Eid Al-Fitr holiday were among those killed, said Jihad Berro, a coroner at a local hospital. He said the medical facility was crammed with victims and their relatives. “The emergency rooms were full, we placed corpses on the floor,” he said. “It is a real catastrophe before the Eid Al-Fitr holiday,” which marks the end of the Muslim holy month of Ramadan, said Berro. An AFP photographer saw a large crowd gathering at the scene of the attack, charred vehicles dotting the side of the road. Rescue workers searched through mounds of rubble, looking for bodies, he said. Resident Abu Youssef said the explosion torched the neighborhood. “The damage is severe: at least six stores were burned, the storefronts of dozens of other stores were blown out,” he told AFP. It was not clear who was behind the attack, which came a day after a similar explosion killed 10 people and wounded 20 in the northeastern city of Raqqa. Turkey launched Operation Euphrates Shield in 2016 and seized more than 2,000 square kilometers of northern Syria including Azaz, clearing the area of Daesh terrorists while preventing any Kurdish advance in the region. Ankara keeps Turkish troops and intelligence forces in the area, and still backs Syrian rebels serving as police officers.