BASEL, Switzerland — Syrian state media and an opposition monitoring group are reporting that airstrikes by the U.S.-led coalition in an eastern town held by the Islamic State group have killed at least 35 people.

The Britain-based Syrian Observatory for Human Rights says 26 people were killed when a four-story building was destroyed in an airstrike. It says nine died in a strike that his a nearby market in the town of Mayadeen on Thursday night.

Syria's state news agency SANA also says 35 civilians, most of them women and children, were killed in the airstrikes.

Reports of deaths among civilians have been on the rise as the fighting against IS intensifies in northern and eastern Syria.