At least five Indian fishermen were apprehended by the Sri Lankan Navy from near Delft Island on Thursday.
These fishermen who had allegedly breached International Maritime Boundary Line are the residents of Pudukottai district in Tamil Nadu.
The navy authorities are conducting an investigation into the matter.
It should be noted that straying of Indian and Sri Lankan fishermen into each other's waters is a recurrent problem as territories on the sea are not clearly demarcated.
In July also, Sri Lankan Navy had arrested four Indian fishermen from Tamil Nadu for allegedly breaching International Maritime Boundary Line and illegally fishing in Colombo's water.