In one of Turkey's worst train disasters, at least four cars overturned near the rural village of Mekece, with most of the damage in two cars that crashed into each other. Bodies lay near the tracks as people climbed on the overturned cars looking for survivors. Darkness hampered rescue operations, with soldiers searching the wreckage and treating the injured by flashlight.

"The train was a little fast going around the curves," said injured passenger Namik Kemal Ozden, lying in his hospital bed with his face bandaged. "There were vibrations. My cousin was sitting next to me. We hugged each other. The windows broke and we fell to one side. We could only understand what happened once we got out."

It was not immediately known what caused the train to derail about halfway to its destination in the capital. But there was opposition when the line started operating June 4, with critics saying the tracks were too old for the new trains.

The crash marked a setback -- and an embarrassment -- in Turkey's efforts to modernise its antiquated rail services. The Istanbul-Ankara train, which cut travel time between the cities from eight hours to five, had been the first step in the government's larger rail system improvement plan. At celebrations to launch the new high-speed line, Prime Minister Recep Tayyip Erdogan wore a station master's cap, blew a whistle and hopped on the train.

At the time, experts had called on the government to modernise the rail infrastructure before allowing the new trains to start running, but the state-run rail authority rejected the criticism and insisted that the old lines were appropriate.

There were conflicting reports of casualties, with the government crisis centre, Health Ministry and Transportation Ministry earlier saying that between 128 and 139 people were killed. The ministries lowered the toll late Thursday without any official explanation.

"A mistake was made in the death and injury toll because of the contradictory information that reached us," said Ayhan Cevik, mayor of the nearby town of Bilecik. "According to the latest information we have, 36 people were killed in the accident and 60 were injured."

The area was devastated by a 1999 earthquake which killed more than 17,000 people, and casualties were rushed to five nearby hospitals equipped to handle disaster emergencies.

Officials initially said they were investigating all possible causes for the accident, but parliament speaker Bulent Arinc later ruled out sabotage. "No officials have any fears concerning sabotage," he said. "There is no such thing.

When it derailed, the train would have been traveling at a normal speed, because the tracks near Mekece were not geared to carry high-speed cars, state railway authority deputy head Ali Kemal Ergulec said.

But survivor Muhittin Anik said he went to the restroom of the train five minutes before the crash and noticed that the speed indicator at one side of the train showed the train to be traveling about 85 mph.

"It really is a fast train," he recalled a friend joking.

At the scene, rescue workers combed through the debris, looking for survivors. Paramilitary soldiers carried luggage from the debris and piled it on the side of the road.

"There were bodies lying all over the place," said Hikmet Feridun Turan, the mayor of nearby Pamukova and one of the first people to reach the scene. "Body pieces. Heads lying on the ground. I don't want anyone to ever see anything like that."

The crash occurred at 7:45 p.m. By midnight, most of the rescue efforts were winding down.

Erdogan cancelled a trip to Bosnia and travelled to the area by helicopter.

Suleyman Karaman, the head of Turkey's railway authority, said a team had been sent to the area to try and determine the cause of the crash. He quoted the conductor as saying the train was traveling at a normal speed and that he "could not understand what had gone wrong."