NEW DELHI: At least 90 people were killed and 105 injured after an Indian express train derailed in northern Uttar Pradesh on Sunday, up from an estimated 60 dead earlier, a senior police official told Reuters.

The death count could rise further as some passengers are believed to be trapped in the wreckage.

Fourteen carriages of the train, travelling between the northeastern city of Patna and the central city of Indore, were thrown off track in Pukhrayan, 65 kilometres south of Kanpur city.

Fourteen carriages of the train, travelling between the northeastern city of Patna and the central city of Indore, were thrown off track in Pukhrayan, 65 kilometers south of Kanpur city, according to railway officials.

"Still many more passengers are trapped," Anil Saxena, a senior railway official in New Delhi told Reuters.

Two senior police officials in Kanpur said their teams have been able to pull out 60 bodies from the badly damaged carriages.

Suresh Prabhu, India's Railways Minister, said in a tweet the government would immediately investigate the causes of the derailment and promised accountability with the "strictest possible action."

India's creaking railway system is the world's fourth largest, ferrying more than 20 million people each day, but it has a poor safety record, with thousands of people dying in accidents every year.

The nation suffers frequent train derailments, sometimes with tragic consequences, including another train accident in Uttar Pradesh in March last year that killed 39 people and injured 150.

Prime Minister Narendra Modi took to Twitter to express his condolences.

"Anguished beyond words on the loss of lives due to the derailing of the Patna-Indore express. My thoughts are with the bereaved families," Modi said.