A rare tornado believed to be the most devastating twister in the Czech Republic’s modern history has torn through country’s southeast, killing at least five people and injured hundreds, rescue services and police said on Friday.

The tornado touched down late Thursday as strong thunderstorms hit the entire country. Seven towns and villages sustained heavy damage that included buildings turned to rubble and overturned cars. The storms were accompanied by hail which in some cases was as big as tennis balls.

Over 40,000 households remain without electricity in the southeastern region of the country.

Some 360 extra police officers were dispatched to the area, along with army troops. Rescue crews from across the country were joined by counterparts from nearby Austria and Slovakia.

They were using drones, helicopters and sniffer dogs to search through the rubble.

Police said at least five people were found dead, but regional government chief Jan Grolich said he would expect the death toll to rise.