MOSCOW -- The Russian Investigative Committee on Sunday classified the bridge collapses in its border regions of Bryansk and Kursk as terrorist attacks.

"The Main Investigative Directorate, on the instructions of the chairman of the Investigative Committee, has initiated criminal cases regarding the explosions on the railway lines in the Bryansk and Kursk Regions. These incidents have been classified as acts of terrorism," said Svetlana Petrenko, the committee spokesperson.

The committee said earlier that two explosions occurred overnight in the two regions, both resulting in bridge collapses and leading to the derailment of passenger trains and causing fatalities.

"On May 31, 2025, at 10:50 pm (0750 GMT), on the Vygonichi-Pilshino railway section in the Bryansk region, an explosion caused the collapse of a road bridge structure," the committee said in a statement.

The explosion caused a passenger train carrying 388 people to derail, resulting in the deaths of seven people and injuries of 66 others, Bryansk Governor Alexander Bogomaz said.

Meanwhile, another blast on a railway bridge in the Kursk region led to a passing train falling onto the road, injuring the driver and two assistants, said the committee.