Four fishermen suffered severe injuries on the head, hand and shoulder while others sustained internal injuries. All of them were admitted to hospital, the sources said.
Two boats and 10 fishing nets were damaged in the attack with bottles, stones and sticks. The Navy personnel also took away the fishermen's catch, the sources said.
"I don’t think our fishermen were at fault today. They have been hit with bottles, stones and sticks in the sea off Dhanushkodi coast. They made futile attempts to contact the Indian Coast Guard personnel," local fishermen's association president Emiret told reporters.
He said the fishermen had enough evidence to prove that they were fishing in Indian waters.
Sri Lanka has often accused Tamil Nadu fishermen of straying into their territorial waters, while the latter maintain they are only fishing in their traditional areas.
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