PAMUKOVA, Turkey, July 22 (AFP) - Nearly 40 people were killed and scores injured when a packed express train crashed Thursday in northwestern Turkey on its way from Istanbul to the capital, Ankara, officials said.
Officials initially put the death toll at 139, but later revised it down to 36.
"As more than one source is trying to determine the number of the dead and injured they may have been exaggerated," Hasan Ipek, the general director of emergency situations at the prime minister`s office told Anatolia news agency.
An AFP photgrapher at the scene said all five carriages of the train overturned when it derailed near Pamukova town in Sakarya province.
Dozens of rescue workers and locals were at the scene combing the area after clearing out the dead and injured from inside the carriages.
"Rescue workers are using heavy machinery to lift up the carriages and check underneath for dead and injured," Pamukova mayor Feridun Turan told the NTV news channel.
"It is total chaos out here," he added.
Anatolia said rescuers, with the help of a sniffer dog, had located a person trapped between the carriages and was trying to extricate him.
Police and paramilitary troops cordoned off the accident site, while the Turkish Red Crescent sent off medical staff and supplies to the region.
There were conflicting reports on the number of those injured which was earlier put at 57.
The transport ministry put their number at 43, while the governor of the nearby province of Bilecik, Ayhan Cevik, was quoted by the Anatolia as saying 60 people were injured.
It was not immediately clear what had caused the train -- on its way from Istanbul to the capital, Ankara -- to derail, but one survivor said he felt the train was speeding.
"On several occasions when taking a turn it trembled a lot and I was hardly able to stand up when I was going to the restaurant," Orcun Acabey told NTV.
"Before the crash, our carriage started shaking violently, leaned to the right and we went on like that for a while," he added.
There were 234 passengers and 12 crew aboard the train.
Anatolia quoted anonymous railway authority officials as saying that most of the casualties were in the first two carriages and that passengers in the remaining carriages escaped unhurt.
Officials refused to say anything on the cause of the accident.
"It is not possible to comment on the cause of the accident before a technical investigation is carried out," Muammer Turker, the head of the railway authority crisis desk, told reporters here.
The train was one of a number of new express trains which came into service last month, offering faster trips between Ankara and Istanbul following renovation on existing tracks. But critics had said the infrastructure was not suitable for such a project.
The trains travel at speeds of up to 150 kilometres (90 miles) per hour, reducing the duration of the trip of 567 kilometres (352 miles) to five hours.
Tha train was supposed to be travelling at a speed of 75 to 80 kilometres at the site of the crash, railway officials said.
"The Turkish railway system has been neglected for the past 50 years. Railway maintainance is insufficient and there are technical deficiencies. In addition, putting fast trains into service carries a risk," Professor Haluk Gercek, an expert on transportation systems at the Istanbul Technical University, told NTV.
But officials dismissed reports the accident might have been caused by the speed of the train.
"We estimate that the fact that the train was upgraded to a fast train did not play a role", Turker said.
Asked whether the train might have derailed as a result of a sabotage, Turker said: "We have to take into account all possibilities. But I cannot say anything about the cause at the moment, because we do not have any findings."