China has finished its first airstrip in the hotly-contested Spratly Island chain in the South China Sea, according to new satellite photos released by IHS Janes.

The airstrip, located on Fiery Cross Reef, is more than 3,000 meters long and appears to be complete due to the new presence of runway heading markings and helipad designators.

Fiery Cross is just one of three reefs in the Spratly group of islands that China has built airstrips on. Currently, airstrips of the same length are under construction on Mischief Reef and Subi Reef.

According to IHS Janes, a defense analysis company, the completion of the runway indicates that China will soon be able to ferry in more supplies and start air patrols over the disputed island chain.

At 3,000 meters long the airstrip can accommodate most Chinese military aircraft, and once the other two airstrips are completed, China will be able to fly near-constant air patrols over the South China Sea.

The islands, once small strips of sand barely above sea level, have been built up in past years as China, using international maritime law, has sought to claim the waters around the islands as their own.

The airstrips are particularly worrying to the Philippines, as they have claimed various islands in the Spratly group as their own. As both the Philippines and China have claimed some of the same territory, close encounters with each other’s navy is an almost daily occurrence.

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 trade route.

While the airstrip on Fiery Cross is a first in the Spratly group, it is not the first airstrip completed in the South China Sea. The Chinese have an airstrip on Woody Island as well.

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