A North East Frontier Railway (NFR) official on Thursday said investigation is underway to determine why the goods train driver exceeded the permissible speed limit before the rake collided with the Kanchanjunga Express at Rangapani in West Bengal.

The Commissioner of Railway Safety (CRS) is probing Monday's accident, which claimed 10 lives, including the goods train driver and the guard of the Kanchanjunga Express.

"What made him go faster than the prescribed speed limit is being investigated," NFR spokesperson Sabyasachi De told PTI over the phone from the zonal railway's headquarters at Maligaon in Assam.

Stating that something might have happened to the driver, which is not yet known, he said this is what the investigation is expected to uncover.

De said the T/A 912 form, which is the basic protocol as per the rule book when there is a snag in the automatic signaling system, was issued to the driver of the goods train.

NFR's Katihar Divisional Railway Manager (DRM) on Wednesday said the automatic signaling system and the train tracking system in the section got disrupted around 5.15 am, following which trains were running under speed restrictions as per rules. The accident occurred at Rangapani around 9 am.

He said the CRS will record the statement of the grievously injured assistant driver of the goods train, Monu Kumar, one of the most important witnesses, when he recovers and is in a position to speak, adding that it may take a few days.

Kumar is undergoing treatment at a private hospital in Siliguri.

Assistant driver Kumar was initially thought to have been killed in the accident by the railway authorities to have died but was later found alive with serious injuries.

The DRM said after recording statements of the witnesses, the CRS will collate those and draw an inference, and thereafter submit a report, which may take some time.

He said as per the memo issued to the drivers in the affected section, the trains were to run at a maximum speed of 10 to 15 km per hour after stopping at every red signal for a minute.

Kumar said the Kanchanjunga Express had halted at one such red signal after crossing Rangapani station when the goods train rammed it.

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