Among the scores of vessels China has sent to protect an oil rig in the disputed South China Sea are two of the PLA Navy's biggest amphibious landing ships and a missile frigate, Vietnamese state media report.
Military experts said the sending of warships to waters also claimed by Vietnam would, if confirmed, indicate Beijing's determination to defend national interests.
The government-owned Vietnam Investment Review yesterday cited the country's Coastguard Command as saying that by the end of Tuesday, China had deployed as many as 86 vessels, including two ships equipped with helicopters, around the drilling rig Haiyang Shiyou 981.
The Jinggangshan and Kunlunshan are 19,000-tonne Type-071 ships and are equipped with eight surface-to-air missile launchers, a 76mm cannon, and four 30mm cannons. They are two of the PLA Navy's biggest amphibious landing ships.
Carrying up to 800 troops, four hovercraft, fast patrol boats and two large Z-8 helicopters, the Type-071 ships are more versatile than any other ship in the modern Chinese fleet.
Macau-based military observer Antony Wong Dong said that besides the two Type-071 ships, a 3,000- tonne landing ship and the 2,400-tonne missile frigate Mianyang had also been sent to the disputed waters. The Mianyang has an anti-submarine helicopter on board.
"It's rare to send out two of the three biggest landing ships from the south sea fleet, as well as other advanced warships, to a disputed water area, meaning China is well-prepared to deal with any possible military conflict with Vietnam," Wong said.
"But I don't think the PLA will proactively open fire, but wait for a chance when the Vietnam coastguard loses patience."
The Vietnamese newspaper said that nine of the 86 Chinese ships were being used to directly protect the rig. It said the China National Offshore Oil Corporation Chinese had been operating near the Paracel Islands since May 1.
Beijing-based military expert Li Jie said Beijing would hold its ground in maritime disputes with Vietnam.
"The oil rig is something equal to China's territory, meaning it's part of core national interests," he said. "It's impossible for Beijing to give an inch."
Additional reporting by Agence France-Presse