A crash involving a high-speed train at a station in the Turkish capital Ankara has killed at least four people and injured more than 40, local media say.
Images from the scene showed emergency services working to rescue people from badly damaged carriages on Thursday morning.
Some reports, citing local officials, suggested that the high-speed train had collided with another train.
The accident occurred at about 06:30 local time (03:30 GMT), says a BBC report.
The train was reportedly beginning a journey from the station in Ankara to the city of Konya in western Turkey.
A large number of emergency workers arrived at the scene shortly after the crash, which occurred in snowy conditions.
In July, 24 people were killed in Turkey when a train travelling from the north-western town of Kapikuleen en route to Istanbul derailed.