DHAKA — At least 17 people have died with many others injured after two trains collided in eastern Bangladesh, authorities say.

A freight train smashed into the rear coaches of a passenger train in Bhairab, 80km (50 mile) north-east of Dhaka on Monday afternoon.

A signal error likely caused the collision, a railway official who asked not to be named told BBC Bengali.

Train mishaps are not uncommon in Bangladesh due to poor infrastructure.

Fourteen people on board the passenger train named Egarsindhur Twilight died on the spot after Monday's collision at the Jagannathpur rail crossing caused three carriages to overturn, BBC Bengali reports. At least two coaches were smashed.

"Many people got trapped inside after the collision. Most of the people died on the spot," the chief of the local fire service, Mohammad Masud, told reporters.

Three others died at the hospital where about 50 injured are being treated. The death toll could climb further as rescue operations are ongoing, Anowar Hossain, superintendent of Dhaka Railway Police told reporters.

A local government official told the BBC that locals had come forward to help the people before rescue teams arrived at the post.

Hospital staff struggled to deal with the influx of injured, prompting them to call for reinforcements from nearby medical facilities.

Bangladeshi authorities have launched a formal investigation into what caused the accident.

Aside from signal error, poor track conditions and unsupervised rail crossings have been blamed for past accidents.

In April, several people were injured after a Dhaka-bound passenger train collided with a freight train in Comilla, south of Bhairab. That mishap was also blamed on a signal error. — BBC