Investigators are trying to find out what caused the fire that swept through a restaurant in Warman, Sask., last night.

People in the town, which is about 20 kilometres north of Saskatoon, said it happened at the Tomas Cook restaurant, which is next door to the Warman Hotel.

Just before midnight Thursday, fire crews responded to a fire alarm at the restaurant. Responders found the building on fire. The adjoining hotel was evacuated.

No one was inside the restaurant and there were no injuries, the RCMP said.

The restaurant suffered extensive damage but the hotel was not affected. The cause of the fire is under investigation.