At least three coaches of the Awadh-Assam Express train were derailed in Bihar's Muzaffarpur district on Monday, disrupting rail traffic on the busy Hajipur-Muzaffarpur rail route, officials said.
No injuries were reported immediately.
The accident occurred near Mirapur railway station and several metres of track were damaged, an official of the East-Central Railway said.
Many trains have been diverted after the derailment.