Satellite images appear to show China’s People’s Liberation Army Navy at Woody Island, the country’s main administrative centre and military base in the South China Sea’s Paracel Islands. The islands are disputed between Vietnam, China, and Taiwan, but are occupied by China, which has built a settlement there.
It is understood the planes are believed to be the Chinese-made variant of the famous Flanker aircraft.
Beijing started using the aircraft in 1998 after China secured a £2.5 billion production agreement with Russian manufacturers.
Under the terms of the agreement, these new aircraft would be outfitted with Russian avionics, radars and engines.
A private satellite image company who took the images, appear to show the planes present at Woody Island on July 15th.
At the same time, the United States deployed two aircraft carriers to the South China Sea.
The US Navy said that the USS Nimitz and USS Ronald Reagan carried out operations and military exercises in the contested waterway between July 4 and July 6, and returned to the region earlier today.
Rear Admiral Jim Kirk, commander of the Nimitz, added: “Nimitz and Reagan Carrier Strike Groups are operating in the South China Sea, wherever international law allows, to reinforce our commitment to a free and open Indo-Pacific, a rules-based international order, and to our allies and partners in the region.”
They stressed that the presence of the carriers was not in response to political or world events.
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China has also held military drills in the sea earlier this month, drawing strong condemnation from both Vietnam and the Philippines.
This was at the same time as the two carriers first crossed the waterway for what the US Navy said were pre-planned exercises.
The Navy has long carried out exercises in the Western Pacific, including in the South China Sea, which extends for some 1,500 km (900 miles) with the navy having three carriers in the region at one point.