BEIRUT, Lebanon — At least 35 people were killed when Russian warplanes attacked a rebel-held village in northwestern Syria, a Syrian war monitor and paramedics said on Friday, making it one of the deadliest episodes in that part of the country this year.

The airstrike Thursday night in the village of Zardana also injured at least 80 people, said the Syrian Civil Defense, a group of volunteer emergency workers known as the White Helmets. Three of the group’s members were killed as they evacuated the dead and the wounded, the organization said.

The Syrian Observatory for Human Rights, which is based in Britain, said the attack occurred after Muslims had broken their Ramadan holiday fast after sunset. The group put the death toll at 44, including six children and 11 women.

Conflicting figures in the aftermath of attacks in Syria are not uncommon. The Observatory said the number could rise, as some victims were still under rubble and some of the wounded were in critical condition.