The commissioner railway safety will conduct the full enquiry, Chennai Divisional Railway Manager S Anantharaman told newsmen.
"If the health condition of the driver (A Rajkumar) permits, he will be questioned. Otherwise, based on doctors' advice, we will take action," he said.
Rajkumar's questioning assumes significance in the wake of railway authorities saying the driver of the MEMU train had jumped a few signals and ignored speed restrictions.
Meanwhile, the Government General Hospital where Rajkumar had been admitted is closely guarded and out of bounds for visitors and the media.
The CRS, southern zone, SK Mittal will conduct an inquiry into the cause of the accident and submit a report in two or three days to the government through the Railway board, said senior divisional safety officer J Christopher Prabhakar.
Railway Minister Dinesh Trivedi had announced a comprehensive probe to ascertain if the accident occurred due to human error or technical fault.
Railway Board Chairman Vinay Mittal had said that according to preliminary report it could be a human error.
"The driver(of MEMU train) apparently had passed a few signals at yellow and a few at red also and has collided with the passenger train waiting for signal clearance at a speed in excess of 90 km per hour," Southern Railway General Manager Deepak Krishnan had said recently.
"Why he has done that we don't know, The driver is very badly injured and apparently just before the impact he jumped out of the train and injured himself," he had said.
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