The Sri Lankan Navy on Wednesday arrested 22 Indian fisherfolk near the Katchatheevu and Neduntheevu islands for allegedly crossing the maritime boundary, The Hindu reported.

They were apprehended in two separate incidents.

The fisherfolk are from Rameswaram and Mandapam in Tamil Nadu and have been taken to Navy ports for questioning, the newspaper reported. Four vessels have also been impounded.

The families of the fisherfolk demanded that they be released immediately.

CR Senthivel, the vice president of the National Fishermen Association, told ANI that the group of fisherfolk from Rameswaram had been fishing between India’s Dhanushkodi and Thalaimannar in Sri Lanka when they were apprehended on claims that “they had fished across the border”.

Katchatheevu is an uninhabited islet in the narrow Palk Strait between India and Sri Lanka. Both India and Sri Lanka had laid claim over the island since at least 1921.

In 1974, the two countries signed an agreement demarcating their maritime boundary. The deal said that the boundary runs one mile off Katchatheevu’s western coast, effectively placing the island in Sri Lankan territorial waters.

However, the dispute has continued to find traction in the politics of Tamil Nadu, especially because it is intertwined with the attacks on and detention of fisherfolk from the state by the Sri Lankan Navy.

Fisherfolk from both countries have been arrested in the past for crossing territorial waters.

In November 2016, representatives from the two countries discussed a proposal to set up a coast guard hotline to prevent further disputes.

The United Nations Convention on the Law of the Sea states that fisherfolk who violate territorial water borders may be warned, or fined, but not arrested or shot at.

The incident on Wednesday came at a time when Sri Lankan President Anura Kumara Dissanayake was in Delhi for the artificial intelligence summit.

The incident also came ahead of the annual festival at the St Antony’s church in Katchatheevu, which will take place on February 27 and February 28. More than 3,000 pilgrims from India are expected to participate, The Hindu reported.

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