A head on collision by two express trains in Southern Poland left 14 people dead and many more injured on Saturday evening.
The accident occurred on the Warsaw-Krakow mainline at the small town of Szczekociny when one of the express trains came on the wrong track.
The tragedy happened at 21:15 local time (20:15 GMT) when a train travelling north from Przemysl to Warsaw collided head on with a southbound train from Warsaw to Krakow.
More than 50 people are believed to be injured in the accident which is one of the "serious rail accidents" in Poland in recent history.
"This appears to be one of the most serious railway accidents in recent years," Slawomir Nowak Transport Minister told the TVN24 news channel.
Prime Minister Donald Tusk reached the spot with his three cabinet colleagues early on Sunday morning.
Passengers are still trapped in the wreckage and helicopter ambulances from Warsaw and Wroclaw are pressed into service to transfer the injured passengers to hospitals.