"Till now we have 17 dead and at least 25 injured, most of them seriously. The injured were admitted to local hospitals," he said.
Sarkar also said the injured were taken to hospital - three of them in serious condition.
There was no major damage to the Ekota Express train, Shafiqul Alam Khan, a spokesman for Bangladesh Railway said.
He said the train originated in the northern town of Dinajpur and that it reached its final stop, Dhaka, a few hours after the accident.
Railway officials have recently blamed faulty signal equipment for increasing numbers of accidents involving trains and other vehicles.