Train accident in Turkey kills four

A train has crashed into an earthmoving machine in northwest Turkey, killing at least four passengers and injuring 17 others, an official says.

Several cars of the train, which was travelling from the capital Ankara to Istanbul, derailed on Thursday, said Gurhan Bilgili, deputy chief of the Bozuyuk fire brigade.

"There are still some passengers stuck in the first car and we are trying to rescue them," Bilgili said.

There were conflicting reports as to how the crash occurred.

Soner Celik, a passenger, told CNN-Turk television that the earth mover was working on a road construction site near the tracks and slid down a hillside, crashing onto to the train. Bozuyuk Mayor Ismail Sagiroglu said the construction machine had carelessly moved onto to the train's path.

The crash occurred 250km from Istanbul.

The worst damage was in the first car, which overturned and was squeezed between the earth-mover and a bridge, the state-run Anatolia news agency reported.

Television footage of the crash site showed rescuers trying to help a man out of a rail car through a window.

There was no immediate information on the condition of the injured passengers.

Turkey's government has been working to improve the country's rail system, which is beset by signalling malfunctions, ill-equipped trains, deteriorating tracks and a lack of barriers at level crossings.

In Turkey's worst train accident in recent years, a newly inaugurated high-speed train from Istanbul to Ankara derailed in 2004, killing 37 people and injuring 95 others.