Lankan Naval personnel also detained a boat belonging to the fishermen for about an hour at the fifth sand dune, which is part of Indian sea territory, Vercode Fishermen Association President Sagayam told reporters and police here.
He alleged that they crossed the International Maritime Border Line (IMBL) and damaged fishing equipment and GPS devices of the fishermen when they were fishing near Aathupalam.
He said the Lankan navy had lined up its patrol boats near Katchateevu to prevent Indian fishermen from crossing the IMBL.
"Our fishermen have been careful as the Sri Lankan navalmen were present in full strength near Katchatheevu, but it was not fair on their part to threaten us at knife point and damage our equipment when we were fishing in our territory," he said.