BEIRUT (AP) — The Latest on Syria's civil war (all times local):

11:15 a.m.

Syria's state news agency says rebel shelling has killed at least four civilians in government-held areas of the contested northern city of Aleppo.

SANA says the shelling on Thursday also wounded four others.

It came just hours after a series of airstrikes hit a hospital and nearby buildings in the rebel-held areas of the city, killing at least 20, including doctors and children.

Aleppo is Syria's largest city and onetime commercial center. It has been bitterly contested since 2012. Opposition groups control the eastern part of the city but have been boxed-in by government forces, and are now linked to the surrounding area by a single narrow corridor to the northwest.

It's in Aleppo that the now-teetering cease-fire has most been tested, and where more than half of the nearly 200 civilians killed in the past week died from the violence.

9:40 a.m.

A Syrian monitoring group and rescue workers in opposition-held areas in Syria say a series of airstrikes has hit a hospital and nearby buildings, killing at least 20 people in the northern city of Aleppo.

The victims include three of the hospital's medical staff.

The head of the Britain-based Syrian Observatory for Human Rights says the airstrikes took place shortly before midnight on Wednesday and that at least one child was among the 20 killed.

The Syrian Civil Defense, volunteer first-responders in rebel-held areas, gave a higher toll, saying the strikes on the Quds hospital killed 22. The dead included one of the few remaining pediatricians in opposition-held areas of the contested city. The Syrian Civil Defense said there were four consecutive airstrikes against the hospital and adjacent buildings.