A fully equipped PLA amphibious task force has reached China's southernmost claimed possession in the South China Sea in an unprecedented show of force that is raising eyebrows across the region. The four-ship flotilla headed by the landing ship Jinggangshan visited James Shoal - some 80 kilometres from Malaysia, less than 200 kilometres from Brunei and 1,800 kilometres from the mainland coast - close to the outer limits of China's "nine-dash line", by which it lays claim to virtually the entire South China Sea. A Xinhua report yesterday described marines and crew gathering on the deck of the Jinggangshan - one of the PLA Navy's three 200-metre landing ships - to pledge to "defend the South China Sea, maintain national sovereignty and strive towards the dream of a strong China". "It was a surprisingly strong message in sending out this task force, on such a new operational role from previous PLAN [PLA Navy] patrols in the region," said Gary Li, a senior analyst with IHS Fairplay in London. "It is not just a few ships here and there, but a crack amphibious landing ship carrying marines and hovercraft and backed by some of the best escort ships in the PLAN fleet," he said, adding that jet fighters had also been used to cover the task force. "We've never seen anything like this that far south in terms of quantity or quality ... it is hard to know whether it is just coincidence, but it does seem to reflect [President] Xi Jinping's desire for more practical operationally based exercises." Youtube video: CCTV footage of Kunlunshan, a PLA Navy amphibious landing ship similar in model to Jinggangshan. The landing ships are considered some of the most sophisticated vessels in the PLA and are thought to be key to any strategy to invade Taiwan. Their deployments are closely watched by regional rivals. The first of the landing ships, Kunlunshan, has been used in anti-piracy work off the Horn of Africa. Photos circulating on mainland websites show marines storming beaches, backed by hovercrafts and helicopters dispatched from the Jinggangshan during several days of exercises that saw them visit all of China's holdings in the Spratly Islands. The PLA took six Spratlys reefs and shoals from Vietnam in a sea battle 25 years ago this month. The ships are due to head back north, crossing into the western Pacific for further drills via the Bashi channel between Taiwan and the Philippines, Xinhua said. News of the Jinggangshan's appearance off James Shoal last night sparked chatter among military officials in the region. "That is quite a show of sovereignty - an amphibious task force," said one military attaché monitoring developments. "It has got everyone talking. The Spratlys is one thing, but turning up at James Shoal is quite another. Once again, China is showing it is quite unafraid to send a message to the region "The Spratlys is one thing, but turning up at James Shoal is quite another. Once again, China is showing it is quite unafraid to send a message to the region - and in a year when Asean is chaired by Brunei, turning up down there in such a fashion is pretty strong symbolism." PLA deployments into the South China Sea in 2009 and 2010 sparked fears across the region of a new assertiveness by Beijing. Those concerns in turn prompted fresh moves by several Southeast Asian nations to force the long-simmering South China Sea dispute back on to the regional agenda - and forge closer ties with the US.