The US-led international coalition carried out a number of airstrikes on al Baghuz Fawqani town of Deir Ezzor province.
According to the source, at least 30 civilians were killed in air raids, dozens of others were injured. The reports say children and women are among the dead. Civilian houses were also damaged.
The number of dead and injured is expected to rise, because there is no capacity to pull victims out of the debris.