India, Oct. 25 -- The National Investigation Agency (NIA) has so far not found any angle of sabotage in the recent accidents on railway tracks, people familiar with the development said on Friday.

The federal agency is probing at least four accidents as part of a preliminary enquiry (PE), they said, adding that the probe is still on.

An official who asked not to be named said on Friday, "We have so far not found any sabotage in the train derailment incidents but the probe is continuing. We are looking into four such accidents as part of a PE."

In the past two months, several cases have come to the fore wherein obstructions in the form of gas cylinders, boulders, or broken rails have been placed on railway tracks with the intent to caus...