The West Zone police have stepped up vigil along the railway line between Tirupur and Erode.
Inspector-General of Police, West Zone P. Sivanandi told The Hindu that following the incident this week, special attention was being paid to prevent such mischief.
Preliminary investigations and the pattern resorted to by the miscreants in all the five instances since 2009 indicate that it was not a sabotage attempt and only an act of mischief.
About 320 police personnel have been drafted exclusively on the job of patrolling. Mr. Sivanandi said that two special teams have been formed to nab the offenders.
The teams have been asked to apprehend the accused within a week.
