An SLR coach of 13226 UP Danapur-Jainagar Intercity Express derailed due to mechanical problems and rammed into an electric post, the sources said.
The driver applied brakes all of a sudden to bring the train to a grinding halt, they said, adding that 12 people, including the guard, sustained injuries even as several passengers jumped off the coach.
Bachhwara Station Manager, Sudhir Rai, and the in-charge of Railway Protection Force's (RPF) nearby outpost, Ramji Yadav, rushed to the spot and took the injured to a hospital for treatment, the sources said.
Train services have been disrupted due to the incident, they said, adding that efforts were on to remove the coach from the track to normalise the situation.