At least 13 people were killed in eastern Deir Ezzor city when the Islamic State struck regime-held neighborhoods with mortar shells and rockets late on Monday, the group's news feeds said.
ISIS has stepped up its shelling on the besieged neighborhoods of al-Joura and al-Qusour in the last few weeks. The overnight attack left also 50 people wounded.
Furat Post, local monitoring group, said three more people had been killed in ISIS artillery on the village of Jazrat Albushams west of Deir Ezzor. The village is held by the US-backed Syrian Democratic Forces.
Syrian regime forces and their allies, backed by Russian air power, have been fighting back against Islamic State assaults in the area.
A mother and her infant were killed in al-Qouriya town by the US-led coalition airstrikes late on Monday.
The U.S.-led coalition has in recent months stepped up targeted raids on the province to rupture the militants' supply lines across Iraq and Syria
