Construction started on Saturday and is expected to take 18 months

China has begun building a school on a remote island in the South China Sea to serve the children of military personnel and others, expanding the rugged outpost it created two years ago to strengthen its claims to disputed waters and islands.

China established the settlement of Sansha which Beijing designates a “city” and has a permanent population of 1,443 on tiny Yongxing island to administer hundreds of thousands of square kilometers of water where it wants to strengthen its control over potentially oil-rich islands that are also claimed by other Asian nations.

Vietnam, the Philippines and the United States criticised Beijing for establishing Sansha, saying it risked escalating regional tensions. The island, also known as Woody Island, is about 350 km south of China’s southernmost province and is part of the Paracel chain, which is also claimed by Vietnam.

Tensions in the area have escalated since China last month placed an oil rig in waters about 30 km from the Paracel Islands, leading to ongoing sea confrontations between Chinese and Vietnamese vessels.

Construction on the school started on Saturday and is expected to take 18 months, the Sansha government said in a statement on its website. It said there were about 40 children of school age on Yongxing Island and that the school could also educate the children of police, army personnel and civilians stationed on the islands, some of whom had to stay with grandparents in far-off hometowns.

When China created Sansha in July 2012, the outpost had a post office, bank, supermarket, hospital and a population of about 1,000. By December, it had a permanent population of 1,443, which can sometimes swell by 2,000, according to the Sansha government.

Now it has an airport, hotel, library, five main roads, cell phone coverage and a 24-hour satellite TV station, according to the government. It also has its own supply ship that brings in food, water, construction materials and people.

In the Philippines, meanwhile, Department of Foreign Affairs spokesman Charles Jose said Sunday that Manila recently protested another land reclamation by China in the McKennan-Hughes reef in the disputed Spratly Islands in the South China Sea.

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