India’s Kalka Mail train crash: death toll reaches 67 (VIDEO)

The death toll from Sunday's train crash in northern India rose to 67 Monday as rescue workers pulled more bodies from the wreckage, the Associated Press reports.

Col. Amarjit Dhillon, a senior army official in charge of rescue operations, told AP that more bodies are believed to be trapped.

The train, called the Kalka Mail, derailed Sunday afternoon near the town of Fatehpur in Uttar Pradesh, a northern state in India. It was about 75 miles from Uttar Pradesh's capital, Lucknow.

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The cause of the accident remains unknown, and railway authorities said they are investigating the accident.

Local media reports said the driver may have tried to avoid hitting cows squatting on the tracks or animals or people walking across the rails and therefore slammed on the train's emergency breaks.

The train was carrying about 1,000 people, and volunteers and soldiers worked through Sunday night pulling out the injured and dead from a dozen coaches. Soldiers were reportedly using gas cutters Monday to break through the metal.

The force of the accident caused some of the carriages to mount each other.

Meanwhile, a second train derailed Sunday in the northeastern state of Assam due to a suspected bomb attack, AFP reports.

Police believe separatist rebels placed a bomb on the tracks, causing the derailment which led to about 100 injured passengers.

The Guwahati-Puri Express was close to Ghograpara outside the capital Guwahati when the bomb struck.

"There was a loud explosion and it was total chaos soon after," a passenger, Jiten Das, told AFP. "The coach in which I was traveling skidded off the track and fell in marshy land with waist-deep water. Somehow we managed to get out. I cut my head and arms and have a wound in my chest."

India's state-run railway system carries 18.5 million people daily. But the aging infrastructure is badly in need of modernization, the New York Times reports. 

Last week, a train crashed into a bus carrying a wedding party, killing at least 33 people.

"There is a real danger that the frequency of train accidents in India might soon desensitise people as 'yet another' instance of what has become thoughtlessly, mind-numbingly commonplace," the Indian Express reportedly said in an editorial Monday.