MOGADISHU (AFP) - At least one Somali pirate was killed and two others wounded after a naval vessel patrolling the Indian Ocean fired on their boat and destroyed their mother ship, witnesses said Thursday.

Local fishermen in the pirate den of Harardhere in northern Somalia said the incident occurred on Wednesday afternoon, but the naval vessel was unknown.

"One pirate died and three others were injured after they approached a navy ship. They were given warning signals but they ignored and kept approaching and their mother boat was destroyed," local fisherman Abdullahi Isa Mohamed told AFP.

Other residents who confirmed the incident said the men were on board small boats hunting for ships to attack.

But the US Navy Fifth Fleet command and the European naval mission off the pirate-infested Somali coast said they had no information regarding the sinking of a pirate mother ship.

The coastal town of Harardhere is often used by Somali pirates to hold hijacked vessels and their crews, releasing them after often hefty ransoms are handed over.

A surge in vessel attacks off Somalia's unpatrolled coast last year prompted the deployment of a multinational naval force to secure one of the world's key shipping routes.

More than 130 merchant ships were attacked in the region last year according to the International Maritime Bureau.