KIEV An explosion and fire that tore through a gambling hall in eastern Ukraine early Thursday killed nine people, the countrys top emergency official said.

Emergency Situations Minister Volodymyr Shandra said 11 more were wounded in the explosion and ensuing fire at the hall, on the ground floor of a five-story building in the city of Dnipropetrovsk.

A preliminary investigation showed a short circuit in one of the halls many slot machines may have been to blame.

In televised remarks from Dnipropetrovsk, Shandra stressed that other explanations, including a bomb, had not been ruled out. The deaths were caused by smoke inhalation, he said.

Because of the explosion, Prime Minister Yulia Tymoshenko canceled a trip to Prague for a summit of former Soviet states, Russian news agencies reported.