SANAA, Yemen (AP) — With combatants fighting in neighborhoods and Saudi-led coalition warplanes pounding Iran-backed rebels from the sky, Yemen’s war is wreaking a particularly bloody toll among civilians: more than 550 have been killed in the past month, including 115 children, the UN said Friday.

Amnesty International said in a new report that some of the airstrikes it examined in the capital of Sanaa and four other cities raise “concerns about compliance with international law,” saying they appeared to have failed to take precautions to avoid civilian casualties.