Trains passing the Uthukuli and Vijayamangalam stations encountered heavy stones and a concrete post on the track on Monday night and early hours of Tuesday. The stones were found in six places.
The ‘cattle guard' fitted on the front side of the engines flung away the stones and pushed aside the concrete post kept on the track.
Railway sources told The Hindu that the first incident occurred around 9.30 p.m. on Monday when the engine of Inter-city Express hit a 5-kg stone.
Minutes later, Kerala Express from Thiruvananthapuram to New Delhi hit a 4-foot-long concrete ‘hectometre post.'
At 10.10 p.m., railway officials found another stone on the track while checking the area.
Even as senior police and railway officials commenced the surveillance of the area, Tea Garden Express hit a stone a few metres from where they were standing in the early hours of Tuesday. Chennai-Alappuzha was the next train to encounter a stone at 3.35 a.m.
Another stone came to the notice of railway police officials while patrolling at 4.25 a.m.
Such incidents had taken place in the last few months on the same stretch.