Rights chief says nearly all deaths reportedly attributable to government forces and allies in Idlib and Hama provinces.

UN human rights chief Michelle Bachelet says her office has tallied more than 1,000 civilian deaths in northern Syria over the last four months, the majority of them due to air strikes and ground attacks by President Bashar al-Assad‘s forces and their allies.

Bachelet, the United Nations High Commissioner for Human Rights, told reporters in Geneva on Wednesday that 1,089 civilians were killed in the war-battered country between April 29 and August 29, including 304 children.

She said nearly all, 1,031 of the deaths, were reportedly attributable to government forces and their allies in Idlib and Hama provinces. Another 58 were caused by “non-state actors,” she said.

Idlib province, which borders Turkey, is the final rebel stronghold in the country.

In late April, Syrian forces, backed by Russia since 2015, began an offensive in the region in an attempt to capture the strategic area, which lies on a key highway connecting Damascus with the northern city of Aleppo.

Bachelet’s spoke hours after Save the Children said in a report that more than half of the children in Idlib province will likely be unable to attend school this year as fighting between rebel groups and government forces destroyed hundreds of learning facilities.

The aid group said 87 education facilities were destroyed and hundreds damaged during months of fighting.

Hospitals and other civilian structures have not been spared from air attacks and shelling.

Idlib is home to three million people, half of whom are already internally displaced from areas previously captured by forces loyal to Assad.

The UN says two-thirds of those currently in the war-torn province are women and children.

A unilateral ceasefire called by Russia on Saturday, which briefly paused the Syrian government advance on rebel-controlled areas, has done little to quell fears of a humanitarian catastrophe.

The ceasefire was yet another attempt to avert a full-blown Syrian offensive, which the UN has said would result in one of the worst humanitarian “nightmares” in Syria’s eight-year conflict.

A previous ceasefire brokered in August ended just days after it began.

Russia intervened in Syria’s long-running conflict almost four years ago in support of Assad, while Turkey has long backed rebels in Idlib. The two countries co-sponsored a de-escalation agreement for Idlib that has been in place since September last year, but faltered in recent months.