Due to the derailment, railway traffic has been affected in the section and a decision has been taken to divert trains, ECR chief public relations officer (CPRO) Rajesh Kumar said.
The good train derailed in between Karmnasa and Dhanaicha in Mughalsarai-Gaya section.
Mughalsarai division forms part of the ECR, with its headquarter at Hajipur in Vaishali district of Bihar.
Railway employees are engaged in clearing the track for resuming normal traffic, the CPRO said.