Security has been stepped up along the Tamil Nadu coast following the arrest of an LTTE "agent" in this temple town late on Saturday night.
On Saturday, the Karnataka police arrested two LTTE supporters in Mangalore.
Police said a man, named Mahendran, was arrested in Rameswaram for "attempting to smuggle diesel for the banned Sri Lankan outfit from Mandapam".
He was spotted with diesel cans and followed by a policeman Saturday night. The man "pulled out a sword and tried to attack the policeman". An attempt to murder case and an attempt to smuggle diesel for a banned organisation has been filed against him.
In December, two men suspected to be members of the LTTE, were arrested in Chennai. Police said they were in India to buy boats for the outfit.
Five other men from Ramanathapuram and Rameswaram were arrested on Dec 11 for allegedly trying to smuggle 'beedi' (hand rolled cigars) into Sri Lanka.
Sri Lankan forces have warned India about smuggling of fuel, medicines, medical personnel and essential commodities for the LTTE from the Tamil Nadu coast.