Rescue workers at the scene of a train crash in the city of Pardubice on June 5.
Four people died, including two Ukrainians, and at least 20 people suffered light injuries in the crash, which occurred after 11 p.m. along the country's main rail corridor from Prague to the east, Interior Minister Vit Rakusan said.
More than 300 passengers were on board when their train collided with the freight train.
Czech TV reported that many of the passengers on board were foreigners. The Prague-Przemysl train is a connection regularly used by Ukrainians traveling between the Czech Republic and Ukraine.
The high-speed passenger train is operated by the private RegioJet company.
Transport Minister Martin Kupka, who traveled with the interior minister to the crash site, told a televised briefing that an investigation into the accident was beginning and it was too early to speculate on its cause.
The corridor in Pardubice, where the trains collided, is vital for Czech Railways.
The drivers in both engines survived, the local CTK news agency said.
Czech Prime Minister Petr Fiala called the crash a major tragedy and offered his condolences to the families of those killed.
A passenger train traveling to Chop in western Ukraine collided with a cargo train in the Czech Republic late on June 5, leaving at least four dead, including two Ukrainians, and over 20 injured, the Czech police and Ukrainian officials said.