Mischief Reef is shown in this satellite image dated Jan. 24, 2012, and provided on Sept. 14. (CSIS Asia Maritime Transparency Initiative/Digital Globe/Handout via Reuters)

China appears to have started building the foundation for a third airstrip in the hotly-contested South China Sea, according to a report Tuesday from Reuters.

The airstrip’s construction, according to the report, appears to have started on Mischief Reef, one of seven artificial islands that China has built.

The chain of islands, both natural and artificial are known as the Spratly Archipelago or Spratly Group. According to the World Wildlife Fund the predominant structure in the small island chain is roughly 600 coral reefs that provide sanctuaries to a wide array of species, some of which are endangered.

In an attempt to take advantage of international maritime laws that provide a certain radius of sovereignty to even the smallest strips of land, China has begun building artificial islands around spats of earth that are barely above sea level in an effort to project maritime power.

[Chinese activity in South China Sea poses complications for Obama]

According to the analysis by the Center for Strategic and International Studies in Washington the construction on Mischief Reef is in line with development on two other “islands.” On both Subi Reef and the reef known as Fiery Cross, China is also in the process of building two 3,000-meter landing strips.

At 3,000 meters the airstrip could accommodate most Chinese military aircraft, according to the report. The placement of three landing strips on the reefs would allow China to conduct almost constant air patrols around the South China Sea.

Photos: China’s rapid island-building strategy continues

The airstrips are particularly worrying for the Philippines, which has also have claimed some of the islands in the Spratly Group and has faced increased levels of harassment from Chinese naval forces in recent years. Brunei, Malaysia, Vietnam and Taiwan also have claims to various parts of the South China Sea, which for all of the claimants, is an important maritime route and fishing ground.

Despite the territorial disputes, Vice Adm. Yuan Yubai, commander of China’s North Sea Fleet, told an audience in London Monday that the body of water undoubtedly belongs to China, simply because of its name.

“The South China Sea, as the name indicated, is a sea area. It belongs to China,” he said.

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