Preliminary investigations have revealed that the Coromandel Express train involved in a horrific rail tragedy in Odisha on Friday entered the loop line and crashed into a goods train parked there instead of the main line just ahead of the Bahanagar Bazar station, a source said.

The coaches of Bengaluru-Howrah Superfast Express capsized after crashing into the coaches of Coromandel Express that had scattered on the adjacent track.

While Coromandel Express was at a speed of 128 kmph, Bengaluru-Howrah Superfast Express was running at a speed of 116 kmph. The report has been submitted to the Railway Board, sources said.

The loop lines of the Indian Railways are constructed in a station area -- in this case, the Bahanagar Bazar station -- to accommodate more trains to ease out the operations. The loop lines are generally 750 metres in length to accommodate full-length goods train with multiple engines.

The two trains were carrying around 2,000 passengers. At least 261 people have been killed in the accident and nearly 1,000 injured.

An eyewitness to the incident, Anubhav Das, also told PTI that local authorities and railway officials had initially indicated that the train he was travelling on -- Coromandel Express -- had rammed into the goods train.

However, none of these accounts was officially confirmed by the railways.

While a thorough probe is underway, none of the authorities has so far talked about any possibility of a sabotage.

The national transporter has initiated a high-level probe into the train crash in Odisha's Balasore, which will be headed by the commissioner of railway safety, South Eastern Circle, officials said.

The commissioner of railway safety works under the Ministry of Civil Aviation and investigates all such accidents.

"A M Chowdhary, CRS, SE Circle, will inquire into the accident," a spokesperson of the Indian Railways said.

The national transporter has also said anti-train collision system "Kavach" was not available on the route.

The crash involved Bengaluru-Howrah Superfast Express, Shalimar-Chennai Central Coromandel Express and a goods train.

"The rescue operation has been completed. Now, we are starting the restoration work. Kavach was not available on this route," Indian Railways Spokesperson Amitabh Sharma said.

The railways is in the process of installing "Kavach", an anti-train collision system, across its network.

Kavach alerts when a loco pilot jumps a signal (Signal Passed at Danger -- SPAD), which is the leading cause of train collisions. The system can alert the loco pilot, take control of the brakes and bring the train to a halt automatically when it notices another train on the same line within a prescribed distance.

While sources had earlier said a signalling failure could be the reason behind the crash, railway officials said it is not yet clear if Coromandel Express entered the loop line and hit the stationary goods train or it first derailed and then hit the parked train after entering the loop line.

The preliminary probe report, a copy of which is with PTI, said the signal was given and taken off for the up main line for train number 12841, the train entered the loop line, dashed with the goods train and derailed. In the meantime, train number 12864 passed through the down main line and two of its coaches derailed and capsized, the report said.

Sudhanshu Mani, the former general manager of the Integral Coach Factory, Chennai and the man who led the team that made the first Vande Bharat train, prima facie ruled out any error on the part of the two loco pilots involved in the tragedy and said the primary reason for the mass casualty is the first derailment and the unfortunate timing of the second passenger train, which came from the other direction at a very high speed.

Mani said if it was just the first train derailing, the LHB coaches would not have capsized and so many casualties would not have been reported.

"Although the reason for the derailment of the first train cannot be a matter of conjecture, as of now, I do not see any evidence of an SPAD case, meaning the driver overriding signals. It was going on the correct path as the data logger shows that the signal was green," Mani said.

In February, close on the heels of a head-on collision between two goods trains in Uttar Pradesh, the railways launched a month-long safety drive to prevent accidents such as derailment and overshooting of signals by loco pilots.

Under the drive, senior officers from the Railway Board, zonal railways and divisions were instructed to visit various sections, lobbies of crews, maintenance centres, work sites etc. and carry out a "thorough review of the working practices" to check and enforce safe operational and maintenance practices prescribed to prevent accidents or unusual incidents Former Member Traffic, Railway Board, Sri Prakash also said the driver of the second train at such a high speed could have done little to limit the damage.

"It basically depends on how much time one has and what speed the train is at for the driver to apply the brakes and stop the train. It is rare for a passenger train to derail while it is most common in case of goods trains. What the investigators find as the cause of the derailment will be key," he said.

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