At least eight carriages derailed at roughly 5.46pm local time, about 80 miles (130km) north of the capital New Delhi, as the train travelled towards the Hindu holy city of Haridwar, police said.
Train crashes are frequent in India, which has the world’s fourth biggest rail network. Poor investment in the vast network and rising demand has left overcrowded trains running on creaking infrastructure.
Saturday’s accident is at least the fourth major passenger train derailment this year and the third in Uttar Pradesh in 2017. A crash in the region in November killed 150 people.
A senior police officer in the state, Anand Kumar, said 20 people had been killed and more than 80 injured.
Sanjeev Balyan, a lawmaker from Muzaffarnagar, the city nearest to the crash, had earlier told Reuters that at least 14 people had been killed.
Ajay Pandey, a senior police officer at the site, said: “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.”
The national authorities have dispatched disaster teams to help.
India’s prime minister, Narendra Modi, sent a message on Twitter saying he was pained by the derailment of the Utkal Express, offering condolences to families of those killed and wishing a speedy recovery to the injured.
The network is in the middle of a $130bn, five-year modernisation. The government launched the additional safety overhaul programme in February after a surge in train accidents in the past two years was blamed on defective tracks.
A senior official in the Uttar Pradesh government, Arvind Kumar, told the Hindustan Times the train driver had slammed the brakes on after spotting maintenance work on the tracks that was not properly signalled.
Anil Saxena, a spokesman for the railways, said it was too early to speculate about any potential cause of Saturday’s crash.
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