An airstrike from an as-yet-unidentified aircraft targeted a mosque in the village of al-Jineh, in the westernmost part of northern Syria’s Aleppo Province, killing at least 42 people, according to the Syrian Observatory for Human Rights. The slain were mostly civilians.
The village, in Atarib District, is rebel held, but that doesn’t necessarily narrow it down all that much as to who was attacking. Syrian and Russian warplanes commonly operate in the area around Jineh, targeting rebels, and US warplanes have also carried out airstrikes nearby against al-Qaeda targets recently.
In smaller villages, it’s not unusual for rebels, particularly Islamist rebels, to organize out of the local mosque, and it’s not unusual for any of the nations mentioned to bomb mosques as a result, despite such attacks commonly having a significant civilian component to them.
ISIS had at one point held the area around al-Jineh as part of its push into the northwestern part of Aleppo, but appears to have been expelled. It is not wholly clearly from public reports at this point which rebels, or coalition of rebels, are there now.