BEIRUT (Reuters) - An attack by Syrian government forces on the rebel-held area of Idlib in northwestern Syria killed at least 15 and wounded several at a displaced persons camp on Wednesday, rescue workers said.

Syria’s northwest corner, including the Idlib region, is the last major chunk of territory still in rebel hands after more than eight years of war.

Ground-to-ground missiles fired from the countryside of Aleppo struck the camp at Kah, a town north of Idlib near the border with Turkey, setting tents ablaze according to the White Helmets, a rescue group known officially as the Syrian civil defense.

The British-based Syrian Observatory for Human Rights said pro-government artillery shelling also hit a maternity hospital in Kah. The Syrian American Medical Society said staff at the hospital were wounded and the hospital damaged.

Russia, which supports Syrian President Bashar al-Assad in his country’s civil war, and Turkey, long a backer of rebels, co-sponsored a de-escalation agreement for the area earlier this year that has since faltered.

The region is home to hundreds of thousands of people who fled other parts of Syria as government forces advanced through the country since Moscow joined the war on the side of Assad in 2015, tipping the conflict in his favor.