CHINA has sent its navy to protect marine archeologists on an expedition that salvaged more than 10,000 pieces of antique porcelain from a sunken junk in a campaign against looters and art smugglers.

It is believed to be the first time that China has deployed its armed forces to stop the plunder of its undersea cultural heritage along the ancient shipping routes, which are known in Chinese as the “silk road of the seas”.

Officials on Hainan Island, in the South China Sea, disclosed that naval vessels and units of the People’s Armed Police had accompanied diving teams on the 55-day mission, which ended last week.

“This ship had been plundered many times since it was first discovered in 1996 by fishermen,” said an official of the Hainan cultural heritage bureau.

“They were stealing everything and the ship was being damaged, so we’ve extracted the remaining relics and plan to raise the vessel later this year.”

Navy gunboats and paramilitary guards escorted boats to and from the diving site in Chinese waters, as the archeologists ferried their finds back to Hainan, he said.

The operation came almost four months after collectors had spent about £2m and sent values soaring at a Sotheby’s auction in Amsterdam of 18th-century Chinese export porcelain which had been recovered legally from another wreck off Vietnam.

The government has decided to raise the stakes in its battle against art smugglers because the rise in China’s own wealth has propelled the price of Chinese antiques to record levels on the world market, dominated by auctioneers in London and Hong Kong.

“Foreign smugglers and antique raiders are using sophisticated salvage equipment to steal China’s undersea treasures,” complained Shan Jixiang, head of the State Administration for Cultural Heritage.

“These criminals are becoming more and more organised, intelligent and ready to use terrorist methods. We want more international help in the protection and recovery of the Chinese cultural heritage.”

Shan said China wanted foreign countries to sign up to agreements to send back illicit items but only four – India, Italy, the Philippines and Peru – had done so.

More than 1,000 sunken vessels are estimated to lie off the coast of just one southern Chinese province, Guangdong, according to a paper from the China heritage project at the Australian National University.

Thousands more may rest at the bottom of the sea along some 50 trade routes which flourished between Chinese ports, Southeast Asia and the Middle East.

These were some of the busiest sea lanes in the medieval world until exports were suppressed by the late Ming emperors in the 17th century, reviving only when early modern Europe discovered a fascination with Chinese art.

The next showdown between the smugglers and the state is likely to take place over a cluster of wrecks found last year off Fujian province, between Hong Kong and Shanghai.

“A lot of people have rushed to raise, steal and smuggle out these underwater relics,” said a recent edict from the provincial government, ordering police and marine border units to intensify checks on speedboats and to apprehend suspicious strangers. Legislators in Fujian have urged the authorities to offer rewards of more than £30,000 for information on thefts and the smuggling of antiques.

Archeologists lament that many wrecks are damaged by treasure hunting fishermen who drop dynamite into the sea, then collect the debris that comes to the surface. Indeed, fragments of seashell encrusted pottery are to be seen at antique markets in Chinese citie They say some salvagers will damage sites or destroy items that might fetch only modest sums in order to drive up the price of higher quality pieces.

The premium for top-level Chinese porcelain can be immense, as Christie’s discovered when Colin Sheaf, then its leading Asian art expert, launched the craze with an auction in 1986 of goods known as the Nanking Cargo, retrieved from a Dutch East India company wreck.

The sale realised £10m in five days and set the tone for a string of similar sales up to the present day. Now that China has woken up to the value of its submerged treasures, the market will become more competitive and political.

Last week Chinese marine archeologists began their most prestigious offshore project yet: the salvage of an 800-year-old cargo ship loaded with treasures from the Song dynasty.

However, attitudes have changed in the 20 years since the ship was first discovered in a joint Sino-British salvage effort. An official from the provincial salvage bureau said: “This is a purely Chinese operation. We have the most advanced salvage equipment in the world. Why let any foreign company join in?”

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