Kerala Police chief Loknath Behra on Friday issued an urgent notice to all the police officials in the 14 districts asking them to be on high alert following an intelligence input.
An alert was issued in Coimbatore, Tamil Nadu that six Lashkar-e-Taiba (LeT) terrorists have entered the state through Sri Lanka.
Behra has asked the police officials to be extra vigilant at bus stations, railway stations, airports, religious places and other sensitive areas as Kerala shares a border with Tamil Nadu at a few places.
As per the information, the group consists of one Pakistani national and five Sri Lankan Tamils.
Behra's notice states that residents should call 112 or the police control room at 0471 2722500, if they notice anything untoward.
Security has been beefed up in the border areas between Kerala and Tamil Nadu.