The sources said that the warplanes bombed heavily a school in the village of al-Sha'afa near the border with Iraq, killing 25 civilians and wounding five more.
They went on to say that several refugee families were living in the school.
Local sources reported on Thursday that the US warplanes attacked the town of Hajin in Eastern Deir Ezzur, killing 12 civilians, most of them women and children.
Meantime, tens of other civilians were wounded, a number of them in critical conditions.
Also, last Tuesday, the US-led coalition fighter jets killed 16 civilians in Southeastern Deir Ezzur.
Local sources confirmed that the US warplanes attacked the town of al-Bahra in Southeastern Deir Ezzur, killing 16 civilians.