Pirate attacks on ships worldwide hit a seven year high in 2010 and a record number of crew were taken hostage, a maritime watchdog body said, despite increased patrolling of the seas.

Somalia remained the biggest problem with pirates operating off the country's shore accounting for 49 of the 52 ships seized last year, an official at the reporting centre of the International Maritime Bureau in Kuala Lumpur said.

The London-headquartered IMB said 1,181 crew members were taken hostage, a record high since the bureau started monitoring piracy in 1991.

The continued increase in these numbers is alarming, said Pottengal Mukundan, director of the piracy reporting centre.

There were 445 actual and attempted pirate attacks on ships around the world in 2010, equal to the last peak recorded in 2003.

The number of attacks in the Gulf of Aden, which along with adjacent seas links Europe to Asia, dropped by half because of better patrolling. But pirates, mostly Somali gangs, struck further away.

All measures taken at sea to limit the activities of the pirates are undermined because of a lack of responsible authority back in Somalia from where the pirates begin their voyages, said Mukundan.

Foreign navies have been deployed off the Gulf of Aden since the start of 2009 and have operated convoys. They have also set up a transit corridor for ships to pass through vulnerable points.

The number of attacks in the South China Sea, which links to a key shipping lane for world trade, more than doubled to 31 in 2010, the IMB said.