"Engines are normally changed at Vridhachalam station. It could have happened here or after (the train left) Salem or Virudhachalam. We are investigating all angles," RPF Salem Railway Divisional Security Commissioner P Rajmohan told reporters in Salem.
He was replying to a question whether the theft could have happened in Salem Junction itself as the train was reported to have halted for five hours (after the loading of the cash) or at Vridhachalam Junction where too some delay was reported.
Rajmohan led a team of RPF personnel and inspected the railway junction in Salem looking for clues into the daring heist of Rs 5.78 crore out of Rs 340 crore cash sent to the Reserve Bank of India from here in three cargo coaches, attached to the Chennai Express.
The theft came to light on Tuesday as four of the more than 200 wooden boxes stuffed with the cash was found ripped open when the train arrived in Chennai.
"We are yet to receive the forensic report. As per the photographs received, we believe the roof of the train was opened by using large sized scissors and not a drilling machine as stated earlier," he said.
As per the initial investigations, the amount had been loaded by bank officials and not by railway officials. "So, we are collecting details of those involved in loading the cash," he said.
"As of now we have received a formal complaint from the bank officials that the money has been stolen. We are taking their statements," he said.