Two Chinese J-11 fighter jets carried out what the Pentagon described as an "unsafe" interception of a US EP-3 spy plane in international airspace over a maritime area claimed by China in the South China Sea.
The incident occurred on Tuesday as the US aircraft carried out "a routine US patrol" according to a Pentagon statement, and came less than a week after China scrambled fighter jets when the USS William P Lawrence sailed close to a disputed reef in the South China Sea.
Chinese official media responded angrily, saying the routine flights were “nothing but blatant provocations against China’s maritime security interests”.
China’s official Xinhua news agency accused Washington of “flexing its military muscle at China’s doormat”.
“Such dangerous and irresponsible activities also significantly increase the risk of military misjudgment in the region,” it said.
The interception is the latest escalation of tensions in the South China Sea, where Beijing's claims over large swathes of territory are contested by nearly all of its neighbours, including Brunei, Malaysia, the Philippines and Vietnam.
China is keen to expand its influence in the South China Sea and it criticises US naval patrols and surveillance flights in the region, while the US accuses Beijing of trying to militarise the region.
Beijing is building airstrips and deploying missiles on man-made islands in the Spratly archipelago and that has increased tensions with Vietnam, the Philippines and Taiwan, all of which claim sovereignty of the islands. More than €4 trillion worth of shipping trade passes through the region annually and Beijing stands accused of trying to militarise the area, although it insists that it is constructing civilian facilities, such as lighthouses.
Last month, the Pentagon asked China to confirm it had plans to deploy military aircraft in the Spratlys after China used a military aircraft to evacuate sick workers from Fiery Cross Reef.
The latest incident comes days before US president Barack Obama travels to Asia for a meeting to include a Group of Seven summit in Japan and his first trip to Vietnam.
Artificial islands
Tensions in the region have mounted in recent months.
Last year, the US Navy sent a guided-missile destroyer on patrol within a 12-nautical-mile exclusion area around one of the artificial islands in the Spratlys, to which Beijing responded by sending a destroyer of their own and a naval patrol ship to the area.
In 2014, a Chinese fighter pilot “buzzed” a US spy plane, prompting an angry response from Washington.
In April 2001, an interception of a US spy plane by a Chinese fighter jet resulted in a collision that killed the Chinese pilot and forced the American aircraft's pilot to make an emergency landing at a base on China's Hainan Island.
In an editorial, China's Global Times newspaper, wrote: "The simmering distrust between China and the US will probably explode if there is another collision. It will be extremely difficult for both sides to control the risks and damage."
The newspaper said the US should step back first. “If Washington denies reasoning, then the South China Sea dispute will become a battle of strength between China and the US, and a game between Washington’s hegemonic ambition and Beijing’s commitment to sovereignty,” it said.