SHANGHAI - China's air force has landed bombers on islands and reefs in the South China Sea as part of a training exercise in the disputed region, it said in a statement.

"A division of the People's Liberation Army Air Force (PLAAF) recently organized multiple bombers such as the H-6K to conduct take-off and landing training on islands and reefs in the South China Sea in order to improve our ability to 'reach all territory, conduct strikes at any time and strike in all directions'," it said in the statement issued on Friday.

It said the pilot of the H-6K bomber conducted assault training on a designated sea target and then carried out take-offs and landings at an airport in the area, describing the exercise as preparation for "the West Pacific and the battle for the South China Sea".

Chinese bombers including the H-6K conduct takeoff and landing training on an island reef at a southern sea area pic.twitter.com/ASY9tGhfAU

— People's Daily,China (@PDChina) May 18, 2018

The notice, published on the PLAAF's Weibo microblogging account, did not provide the precise location of the exercise.

The United States has dispatched warships to disputed areas of the South China Sea in a bid to challenge China's extensive sovereignty claims in the territory, which is subject to various claims by China, Vietnam, the Philippines, Taiwan, Brunei and Malaysia.

"The United States remains committed to a free and open Indo-Pacific," Pentagon spokesman Lieutenant Colonel Christopher Logan told Reuters.

"We have seen these same reports and China's continued militarization of disputed features in the South China Sea only serves to raise tensions and destabilize the region."

The Asia Maritime Transparency Initiative (AMTI) said China has built large hangars in the Spratlys and future deployment to the so-called Big 3 outposts--Subi, Mischief, and Fiery Cross Reef--would bring Singapore and much of Indonesia within range of China's lower-end bombers.

"The base H-6 aircraft’s combat radius of nearly 1000 nautical miles means even China’s basic bombers taking off from Woody Island could cover the entire South China Sea."

"Nearly all of the Philippines falls within the radius of the bombers, including Manila and all 5 Philippine military bases earmarked for development under the US-Philippines Enhanced Defense Cooperation Agreement," the think-tank said.

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