A three-story girl`s dormitory collapsed in central Turkey early Friday, killing 13 students and injuring at least 20, a local emergency services official said. An estimated six other students were still under the rubble according to CNN.

A large gas canister explosion is believed to have caused the collapse in the village of Balcilar in Central Konya province, said Mayor Mehmet Demirgul.

Besides the fatalities, at least 20 students were brought out of the debris with injuries, said Galip Sef, an official with the local emergency services. Three of the students sustained severe burns, he said.

Demirgul said an estimated six more students were waiting to be rescued.

An estimated 40 girls, aged between 8 and 16, were staying at the dormitory. The students were attending Quran courses during the school summer break.

Television footage showed local residents, some using their bare hands, trying to remove the rubble from a flattened, concrete building.

One girl in pajamas could be seen being carried to a hospital. Another could be seen being treated on the back seat of a van, before being moved onto a stretcher and taken away, groaning in pain.

Demirgul said authorities believe the building collapsed when the gas canister used in the canteen exploded.