Four people died and more than 20 were injured when a passenger train collided with a freight train in the Czech city of Pardubice late on Wednesday, emergency and government officials said.

At least 20 people suffered light injuries and another three were more seriously hurt in the crash which occurred after 11 p.m. (2100 GMT) in Pardubice, along the country’s main rail corridor from Prague to the east, Interior Minister Vit Rakusan said.

The passenger train, operated by RegioJet, was travelling overnight from Prague to Kosice in eastern Slovakia, according to the Railway Administration.

Fire Rescue Services said more than 300 passengers were on board. Dozens of police, fire and emergency service units responded to the accident, helping evacuate carriages.

Footage after the crash on news website idnes.cz showed at least one carriage off the track, while police showed on their X social media account a line of emergency service vehicles and a helicopter.

Czech Television cited a fire brigade spokesperson saying the freight train was carrying calcium carbide, although the first two wagons were empty, so no leak occurred.

Transport Minister Martin Kupka, who travelled with the interior minister to the crash site, told a televised briefing an investigation into the accident was beginning and it was too early to speculate on its cause.