Explosions caused two bridges to collapse and derailed two trains in western Russia, officials said, without saying what had caused the blasts. In one of the incidents, seven people were killed and dozens were injured.

Hours later came a report of another bridge collapse, also in western Russia, involving a freight train. A bridge overpass in western Russia collapsed late Saturday, derailing a passenger train underneath and killing at least seven people and injuring dozens, officials and the state news media said.

At least seven people were killed after Russian officials said “illegal interference” caused a bridge to collapse and a train to derail in Russia.