An electric locomotive ran over a concrete clab placed on a railway track near Pattabiram railway station here early this morning, but no damage was reported, officials said.
The locomotive, running on the Arakkonam-Chennai sector, ran over the slab and broke it into pieces, police said.
The engine driver alerted higher officials, who rushed to the spot and conducted inquiries.
Railway officials and forensic experts said after preliminary investigation that it could perhaps be the handiwork of miscreants or any banned outfits.
Railway authorities have ordered a detailed probe into the incident.
It may be recalled that passengers of the Tiruchi-Chennai Egmore Rockfort Express had a narrow escape recently after the railway track was found cut near Perani railway station of Villupuram district.