Indian authorities said they had concluded rescue operations on Sunday after the country's deadliest rail crash in more than two decades, with signal failure emerging as the likely cause of death for at least 275 people.

The death toll from Friday evening's crash was revised down from 288 after it was found that some bodies had been counted twice, said Pradeep Jena, chief secretary of the eastern state of Odisha.

The tally is unlikely to rise, he told reporters. "Now the rescue operation is complete."

But nearly 1,200 were injured when a passenger train hit a stationary freight train, went off the tracks and hit another passenger train passing in the opposite direction near the district of Balasore.

State-run Indian Railways, which says it transports more than 13 million people every day, has been working to improve its patchy safety record, blamed on ageing infrastructure.

Prime Minister Narendra Modi, who faces an election due next year, visited the scene on Saturday to talk to rescue workers, inspect the wreckage and meet some of the injured. "Those found guilty will be punished stringently," Modi said.

PRELIMINARY INVESTIGATION

A preliminary investigation indicated the Coromandel Express, heading to Chennai from Kolkata, moved out of the main track and entered a loop track – a side track used to park trains – at 128 kph (80 mph), crashing into the freight train parked on the loop track, said Railway Board member Jaya Varma Sinha.

That crash caused the engine and first four or five coaches of the Coromandel Express to jump the tracks, topple and hit the last two coaches of the Yeshwantpur-Howrah train heading in the opposite direction at 126 kph on the second main track, she told reporters.

This caused those two coaches to jump the tracks and result in the massive wreckage, Sinha said.

The drivers of both passenger trains were injured but survived, she said.

RESTORATION

Workers with heavy machinery were clearing the damaged track, wrecked trains and electric cables, as distraught relatives looked on.

More than 1,000 people were involved in the rescue, the Railway Ministry said on Twitter.

"The target is by Wednesday morning the entire restoration work is complete and tracks should be working," said Railway Minister Ashwini Vaishnaw.

At a business centre where bodies were being taken for identification, dozens of relatives waited, many weeping and clutching identification cards and pictures of missing loved ones.

Kanchan Choudhury, 49, was searching for her husband at the centre. Five people from her village were on the train, four of them being treated at the hospital for injuries. Her husband was found dead, she said, weeping as she waited to claim compensation, carrying her and her husband's identity cards.

Families of the dead will get 1 million rupees ($12,000) in compensation, while the seriously injured will get 200,000 rupees, with 50,000 rupees for minor injuries, Vaishnaw said on Saturday.

Pope Francis, U.S. President Joe Biden, Canadian Prime Minister Justin Trudeau, British Prime Minister Rishi Sunak and French President Emmanuel Macron have expressed condolences.

(Reporting by Jatindra Dash and YP Rajesh; Additional reporting by Jayshree Upadhyay; Writing by Ira Dugal; Editing by Robert Birsel, Sonali Paul and William Mallard)