A government airstrike hit a school Wednesday in the northern Syrian city of Aleppo, killing at least nine people, including three children, activists reported.

A government airstrike hit a school Wednesday in the northern Syrian city of Aleppo, killing at least nine people, including three children, activists reported.

The airstrike hit the Ein Jalout school in an eastern neighborhood of Aleppo, said the Britain-based Syrian Observatory for Human Rights and the local Aleppo Media Center.

Both reported the same death toll, but said numbers were expected to rise because of the extent of the explosion.

The school appeared to have been hosting an exhibition of children’s paintings when the airstrike hit, according to a man speaking in a video from the school that was posted online. Another video showed colorful scrawled paintings. The videos appeared genuine and corresponded to Associated Press reporting of the event.

The attack is the latest deadly government strike against rebel held districts in Aleppo. Forces loyal to Syrian President Bashar Assad have been trying to take eastern rebel-held parts of Aleppo from rebels in recent weeks, using a mix of airstrikes and dropping crude barrel bombs on opposition areas.

The strikes frequently strike residential areas, hitting schools, mosques and markets.

A Syrian government airstrike last week struck a vegetable market in a rebel-held town in Aleppo province, killing at least 30 people and wounding scores others. Rebels have hit back with mortar strikes and car bombs.

On Tuesday, a massive double car bombing and a mortar strike targeted pro-government districts in Damascus and Homs, killing at least 54 people.

Videos of Wednesday’s attack showed bulldozers trying to remove rubble from parts of the smashed school. They also showed the school’s name.

One painting on a still-standing wall in the smashed school showed a skeleton hanging, with skulls littered below in stark white-and-red. Nearby, a child is being shot by a gunman in a ditch. The child has a speech bubble written above her head in broken English that partly reads: “Syria will still free.”

A Syrian activist from Aleppo now based in Berlin sent the AP an invitation for the exhibition to show it was being held at the school at the time of the strike.

Meanwhile, a coalition of rebels, mostly from hard-line Islamic groups, have been attacking government-held parts of Aleppo, firing mortars into residential areas, which have killed civilians.

The Observatory, which bases its information from a network of activists on the ground, says thousands of Syrian children have died in the 3-year-old conflict. The Syrian war began as an uprising against Assad’s rule, but has now become a civil war that has killed over 150,000 people and displaced millions.