An official says a powerful tremor has killed three men working in a coal mine in the Czech Republic.

Marek Sibrt, a spokesman for the OKD mining company, says the miners died late Friday morning, 900 meters (2,953 feet) below the surface at the CSA mine in Karvina, 360 kilometers (200 miles) east of Prague.

Sibrt says nine other miners working at that location escaped with injuries that were not life threatening.

No other details, including the identities of the victims, were immediately released.