Chennai, Sep 23 (IANS): Tamil Nadu Chief Minister J. Jayalalithaa has urged Prime Minister Narendra Modi to take steps to secure the release of 15 Indian fishermen and 28 fishing boats from Sri Lankan custody.

In a letter to Modi on September 22 the text of which was released to the media on Wednesday, Jayalalithaa said 15 fishermen in two fishing boats from Nagapattinam fishing base in Tamil Nadu were apprehended by the Sri Lankan Navy on September 21 and taken to Kankesanthurai in Sri Lanka.

She said the latest apprehension of innocent and unarmed Tamil Nadu fishermen is to intimidate and prevent them from venturing into their traditional fishing waters in the Palk Bay and in the vicinity of Katchatheevu.

"Further, as you are aware, as on date, 26 fishing boats belonging to our fishermen still continue to be in Sri Lankan custody," Jayalalithaa said.

Reiterating her demand that India abrogate the 1974 and 1976 agreements with Sri Lanka ceding Katchatheevu, Jayalalithaa urged Modi to take concrete steps to secure the release of the fishermen and boats.

Katchatheevu island is located in the narrow sea dividing the two countries. The sea near the islet is said to be rich in marine life, leading to frequent clashes between Indian and Sri Lankan fishermen.