Five people were killed in an explosion at a hospital in eastern Ukraine on Monday, the emergency ministry said, DPA reported.

It was not clear how many people were injured in the blast at the hospital in the city of Luhansk that was believed to have been caused by the accidental denotation of a gas cylinder, according to the ministry.

Rescue workers were searching through rubble on four floors of the 11-storey hospital for at least seven people still thought to be trapped, according to news reports.

The explosion destroyed an intensive care unit. Three survivors reached by rescue workers were receiving treatment for injuries, the Interfax news agency reported.

Prime Minister Yulia Tymoshenko was planning to fly to Luhansk on Monday.