Two firefighters were killed in a gas explosion that leveled a family house in southeast Czech Republic, officials said on Wednesday.

The head of the regional government, Radim Holis, also said two other firefighters were injured. The regional rescue service said a total of four people were injured in the explosion that occurred in the town of Korycany shortly after noon.

One was taken to hospital for treatment by a helicopter.

The rescuers used a sniffer dog to search the rubble.

The firefighters said they were called to the house due to leaking gas that, however, exploded after their arrival.