Two of the coaches telescoped into each other, while four others toppled over after going off the track, said Arvind Kumar, a top official in Uttar Pradesh, the state where the derailment occurred.
Neeraj Sharma, a railway spokesman, said the incident took place near the small town of Khatauli.
The cause of the derailment was not immediately known, Sharma said.
Railway police and local volunteers helped pull passengers out of the upturned coaches of the Kalinga-Utkal Express, which connects the Hindu holy city of Haridwar with the temple town of Puri, in the eastern state of Orissa.
“We are struggling to pull out injured, and are waiting for gas cutters to arrive. It’s too dark to launch a full-fledged search operation, but our teams are trying their best,” senior police officer Ajay Pandey told Reuters news agency.
Indian Prime Minister Narendra Modi said on Twitter that he was pained by the derailment and offered condolences to families of the victims.
Reuters reported in June, citing two government documents, that a planned $15 billion safety overhaul of India’s ageing rail network faced delays as the state steel company was unable to meet demands for new rails.
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