Chennai: Voicing concern over the arrest of Indian fishermen by Lankan navy in the 'vicinity' of Katchatheevu, Tamil Nadu government has once again raised the demand that India 'retrieve' the islet from Sri Lanka.

In a letter to Prime Minister Narendra Modi, Chief Minister Jayalalithaa said 15 fishermen, who set sail from Nagapattinam, were apprehended by the Lankan navy on September 21 and sought steps for their immediate release along with 28 boats that are in Lankan custody.