A three-member technical team of senior railway officials from the Signal & Telecom, Engineering and Operations department raised serious apprehension of sabotage after inspecting the accident site at Kavaraippettai Railway Station in Tamil Nadu, railway sources said.

On October 11, train No12578 Mysuru - Darbhanga Bagmati Express collided with a stationary goods train at around 8.30 pm at Kavaraippettai Railway Station in Chennai Rail Division, Tamil Nadu, causing injuries to nine passengers.

"The team of senior officials have found that the mechanical parts of the interlocking system were opened. Normally, these parts get broken after an accident due to the heavy impact of the locomotive and coaches," a source, close to the inspection team, said.

"It looks like the miscreants, who interfered with the interlocking system, gained knowledge from some well-trained person and tried doing it elsewhere earlier for experience," he added.

The Railway officials said that some cases were reported earlier from different places near Kavaraippettai Railway Station where the miscreants tried to subvert the interlocking safety system but couldn't do it.

"Perhaps they gained experience by doing that elsewhere and finally implemented their plan successfully in Kavaraippettai. The interlocking system was subverted within a few minutes as the previous train which crossed the said interlocking point was four minutes before the Mysuru-Darbhanga Express," the source said.

The Railway officials said that after examining the condition of the site, it seemed that there was no defect in the signalling system or any error on the part of the signalling department.

"Initially, it looked like the signal was given for the main line but the interlocking was done for the loop line due to which the passenger train entered the loop line and rammed into the stationary freight train. However, now the shreds of evidence observed at the site suggest something else," a railway official said.

"Now it seemed that as the interlocking point was subverted, there is a strong possibility that the train derailed first at the interlocking point and then due to its high speed headed towards the freight train and collided with it. That could be the reason why the loco pilot reported a huge jerk at the interlocking point," he added.

Earlier, a section of safety experts after analysing the data logger's yard simulation video had also raised the possibility of derailment of the Mysuru-Darbhanga Express at the interlocking point.