• This is the first official confirmation the J-20 was operating over such a wide area
  • The statement revealed the jets were deployed to the Southern Theatre Command
  • The U.S. Navy was recently left "impressed" after a "close encounter" with J-20s

China has started sending its most advanced and domestically-developed stealth fighter jet, J-20, into the East and the South China Sea.

The fighter, christened Mighty Dragon, was said to have left the U.S. Navy "impressed," following a "close encounter" a few months ago.

This is the first official confirmation that the People's Liberation Army's most advanced warplane is operating over such a wide area, reported The South China Morning Post.

"The J-20 has switched to a ‘Chinese heart’ and it has become a training routine to conduct combat patrols in the East China Sea and alert patrols in the South China Sea,” Ren Yukun, a senior official from the state-owned Aviation Industry Corporation of China, told reporters Tuesday.

The manufacturer's statement refers to early versions of engines used in the J-20, which were recently upgraded with new thrust-vectoring nozzles replacing the WS-10C stopgap engines. The jets fitted with domestically-produced twin engines were recently displayed at an air show in China.

Ren's statement also highlighted the fact that the Mighty Dragons have been deployed to the Southern Theatre Command, which covers the South China Sea. Earlier reports had mentioned the J-20s were operating only under the Eastern Command, which oversees the Taiwan Strait and Senkakus.

The fighter jet's deployment in the South China Sea was also confirmed by the Chinese state-backed Global Times, which said the move "will enable the advanced warplane to better safeguard China's airspace security and maritime interests." The Beijing-based media also quoted a military expert who said the fighter will "appear on potential battlefields, including at sea, particularly when advanced warplanes of the U.S. like the F-35 and the F-22 have been flying near China."

According to military experts, the deployment of the J-20s is a warning to other countries, which have a claim over the disputed waters.

"The PLA now has in regular service a fleet of advanced stealth fighters as good as the Americans, who remain the benchmark," Peter Layton, a visiting fellow at the Griffith Asia Institute in Australia, told CNN. He added China's message to the world is: "Any foreign military aircraft intruding into China's claimed airspace in the East and South China Sea may now be intercepted by J-20s."

Post its upgrade, the J-20 was expected to take on the U.S.-made Lockheed Martin F-22 Raptor. Recently, a top U.S. Air Force officer also revealed how American Lockheed Martin F-35s had a close encounter with China’s J-20 stealth fighters recently in the East China Sea.

Gen Kenneth S. Wilsbach, Commander of the Pacific Air Forces, said the encounter left the U.S. "impressed."

"They are flying it [J-20s] pretty well. We recently had – I wouldn’t call it an engagement – where we got relatively close to the J-20s along with our F-35s in the East China Sea and we're relatively impressed with the command and control that was associated with the J-20," Wilsbach said about China's prized fighter.

China's J-20 aircraft
Representation. China's J-20 stealth fighter during an air show. Reuters