BALASORE, India: Passenger and freight trains were running again on Monday at the site of India’s deadliest train disaster in decades, which officials said was caused by failures linked to signal systems.

Trains rumbled past the debris of smashed carriages from last Friday night’s crash near the city of Balasore in the eastern state of Odisha, where at least 275 people were killed and hundreds injured.

Officials initially reported 288 deaths, but the Odisha state government has since revised the toll to 275 after some bodies were mistakenly counted twice.

Of the 1,175 injured, 382 were still being treated in the hospital, authorities said on Sunday.

However, many fear the death toll could still rise, with medical centers overwhelmed by the number of casualties, many of them in serious condition.

Green netting was erected on either side of the tracks, shielding the crumpled carriages pushed down the embankment from the view of traveling passengers.

Railways Minister Ashwini Vaishnaw was seen folding his hands in prayer as he saw the first train cross the site of the disaster on Sunday night.

His ministry said the first train — a train loaded with coal — started 51 hours after the crash.

It was not immediately clear if all the tracks had been fully repaired, with trains on Monday using only lines on one side.

There was confusion about the exact sequence of last Friday’s events, but reports cited railway officials as saying a signaling error had sent the Coromandal Express running south from the city of Kolkata to the city of Chennai onto a side track.

It slammed into a freight train and the wreckage derailed an express running north from India’s tech hub Bengaluru to Kolkata.

Vaishnaw said on Sunday the crash happened due to the “change that occurred during electronic interlocking,” referring to a technical term for a complex signal system designed to stop trains colliding by arranging their movement on the tracks.

“Whoever did it, and how it happened, will be found out after proper investigation,” he added.

Prime Minister Narendra Modi visited the crash site and injured passengers in the hospital last Saturday and said “no one responsible” would be spared.

Of those injured, the most critical patients had been moved to bigger hospitals in cities further away from the crash site. However, many crash survivors were still being looked after at the main government hospital in Balasore.

Gura Palai, 24, a laborer from Jharkhand state, suffered serious injuries to his leg and shoulder. His family was overjoyed he had survived, but worried for the future.

“He has to undergo an operation on his leg, and the doctors say that the recovery will take some time,” said his uncle, who did not give his name, standing next to his bed in a cramped orthopedic ward alongside Palai’s wife and child. “He is the only earning member of his young family. How will they survive?”