In yet another mid-sea attack, Sri Lankan Naval personnel allegedly hurled petrol bombs at a group of fishing boats from here, sinking one of them and damaging 20 others near Katchatheevu in the Palk Strait, officials said on Thursday.

The fishermen, who had put out to sea from here, came under the attack around midnight on Wednesday while they were fishing near Katchatheevu, fisheries department officials said.

They said the Sri Lankan Naval personnel hurled petrol bombs at two boats. One of the vessel owned by one Arumugam sank while another narrowly escaped. Four occupants of the sunk boat were rescued by the others and brought to the shore.

Twenty other boats suffered damage when the Lankan Navalmen attacked them with a variety of missiles inlcuding bricks, rocks, they said.

The incident comes close on the heels of the March 10 attack allegedly by Sri Lankan Naval personnel in which 16 fishermen were injured.

India then had asked its mission in Colombo to take up the issue of attack on the fishermen with the authorities in Sri Lanka.

Condemning the latest attack, Rameswaram Fishermen Association President N Devadoss demanded that External Affairs Minister S.M.Krishna take up the issue with the United Nations and lodge a strong protest.

"Unfortunately he (Krishna) has been keeping quiet as if nothing is happening to the Indian fishermen," Devadoss said.