Security has been beefed up in all Kerala bound trains from Tamil Nadu following an anonymous call that bombs would explode in them.
"Passengers bound for Kerala were thoroughly frisked at the Central Railway station with the help of bomb detection squad and police personnel", Southern Railway protection force sources said.
The call was received by Kerala police and the man was identified as one Mohammed Yusuf, a native of that state, they said.
Trains from Kerala to various destinations in Tamil Nadu were also stopped at various stations, including Coimbatore, Erode, Salem, Tirunelveli and Nagercoil and were thoroughly checked.
Officials said no bombs or explosives had been found so far
The heightened security measures would continue till tomorrow, they added.