Three Chinese navy ships, armed with special forces, helicopters and missiles, are on their way to join the international anti-piracy task force patrolling the waters off Somalia.

The three vessels - two destroyers and a supply ship - will sail from the southern island province of Hainan later today. China announced it was joining the anti-piracy mission on Tuesday after the UN Security Council authorized nations to conduct land and air attacks on pirate bases.

It marks a break in tradition for the modern Chinese navy, which usually confines itself to patrolling coastal waters.

It has been spurred into wider action by the escalation of pirate attacks on merchant ships, including Chinese vessels, plying the shipping route linking Asia and Europe.

The three vessels - the missile-armed destroyers DDG-171 Haikou and DDG-169 Wuhan and the Weishanhu supply ship - are among the most sophisticated in the Chinese navy, all entering service this decade, the Xinhua news agency said.

China's willingness to send ships so far from home is the latest example of the growing power and confidence of the country's navy.

In recent years, the military has been stocking up on warships, planes, missiles and other weapons — a beef-up that has worried its neighbors.

The US and Australia have both expressed concern about China's military build-up and its lack of transparency. Kevin Rudd, Australia's Prime Minister, warned recently that Asia was in the grip of an arms race.

Denny Roy, a senior fellow at the East-West Center in Hawaii, said while the move was a positive sign that China was willing to use its fire-power for constructive purposes, it raised unsettling questions over the country's military buildup.

"The Chinese deployment gets at a question the US and other governments have been asking: 'Why the big Chinese military buildup when no country threatens China?' Or more bluntly, 'Why do the Chinese need a blue-water navy when the US Navy already polices the world's oceans?' he asked.

China has said the mission's purpose was to protect Chinese ships and crews that have come under attack from pirates.

The vessels would also be willing to share intelligence and conduct humanitarian rescue operations with other countries involved in the anti-piracy efforts, Senior Colonel. Huang Xueping, spokesman of the Ministry of National Defense, said.

The two Chinese destroyers — the Haikou and Wuhan — will carry special forces, two helicopters and traditional weapons such as missiles and cannons. Colonel Huang did not say how long the mission will last, but a Communist Party newspaper has said the ships would be away about three months.

Pirates have made an estimated $30 million hijacking ships for ransom this year, seizing more than 40 vessels off Somalia's 1,880-mile coastline.

On Thursday, a German military helicopter rescued an Egyptian ship from pirates who shot and injured a crew member while trying to board the vessel off the Somali coast, said Noel Choong of the International Maritime Bureau's piracy reporting center.

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