After a preliminary inquiry by the Railways showed a possible failure of the electronic interlocking system to have led to the three-train collision near Balasore in Odisha, Railways Minister Ashwini Vaishnaw ordered a CBI probe into the matter.

In what is seen as one of the worst rail accidents in the country in recent times, at least 270 people died and a few hundred where left injured when two passenger trains and one goods train was involved in a collision in the eastern state of Odisha on Friday evening,

“Considering the sequence of events, the manner in which the matter unfolded and the inputs we have got from the district administration, the Railway Board has recommended a CBI investigation,” Vasihnaw said on Sunday evening indicating that the matter will be referred to the investigating agency.

Change in Electronic Interlocking

Earlier in the day, the Minister had said preliminary reports suggested an issue with the change in electronic interlocking. The Commissioner of Railway Safety, South Eastern Railway, is already carrying out a probe in the matter.

Electronic interlocking is the computer-controlled track management system and is called “interlocking system”. It directs a train to an empty track at the point where two tracks meet; coordinates and controls the signal of an oncoming train, indicating whether the train has to move straight or switch to a new track.

“The cause of the accident has been identified. And the people have been identified ...It is about point machine, electronic locking. The accident reportedly happened at the time of change of electronic interlocking. Whoever did it and how the accident happened will be found out after proper investigation,” he said.

Vaishnaw said work is on to restore normalcy in the route by June 7. While the Up and Down lines have been restored on Sunday; work on overhead electric lines are on.

Signal failure?

According to Railway Board Members, prima facie indications are towards a signalling failure. The probe, they said, will also look at the failure of the track management system and other possible angles.

The track management systems is supposed to be tamper-proof, error-proof. It is called a fail-safe system, even if it fails the signal will turn red and the train will be stopped,” said Jaya Varma Sinha, a member of the Railway Board adding that:

“However, as it is being suspected, there was some kind of a interference with signalling system,” she said. Such interference can occur because of human error, weather issues, communication failure or otherwise, those aware said. The exact reason for the suspected failure “remains unknown”.

Asked if the Railways suspected foul play, Sinha said: “Nothing is being ruled out.”

As per the sequence of events released by the Indian Railways, the Coromandel Express heading to Chennai from Kolkata moved out of the main track, entered a loop track – a sidetrack used to park trains – at a speed of 128 kmph and crashed into a freight train carrying iron ore that was parked on the loop track. The crash caused the engine and the first four or five coaches of the Coromandel Express to jump the tracks, topple and hit the last two coaches of the Yeshwantpur - Howrah Superfast train heading in the opposite direction on the second main track.