Explosions caused two bridges to collapse and derailed two trains in western Russia overnight, officials said on Sunday, without saying what had caused the blasts.

In one of the incidents, seven people were killed and dozens were injured.

The first bridge, in the Bryansk region on the border with Ukraine, collapsed on top of a passenger train on Saturday, causing the casualties.

Hours later, officials said a second train was derailed when the bridge beneath it collapsed in the nearby Kursk region, which also borders Ukraine.

Rescue workers at a damaged bridge in Russia’s Bryansk region, which borders Ukraine (Moscow Interregional Transport Prosecutor’s Office telegram channel/AP)

In that collapse, a freight train was thrown off its rails on to the road below as the explosion collapsed

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