A powerful explosion in the Turkish capital collapsed two stories of a factory Thursday, leaving at least six people dead and injuring some 30 others.

Search and rescue teams combed the rubble of the building in the industrial area of Ankara for workers who may be trapped inside. "Our hope is that there are no other deaths inside the ruins," Interior Minister Besir Atalay told reporters at the scene.

Atalay initially said four people were killed in the explosion, but later raised the death toll to six.