They have the potential for blocking free passage of South China Sea in a way that they'll be difficult to remove - They're already interfering with over flights and fishermen.
"Under the UN Convention on the Law of the Sea (Unclos), which was ratified by China, it cannot claim reefs and other structures below the sea’s surface as sovereign territory, nor anything built on top of them.
A border of 12 nautical miles can be claimed at sea and in the air around natural islands but as many of China’s reefs in the Spratly Island do not meet that definition, they are not its territory and borders cannot be enforced.
But the international laws seemed to be ignored when the BBC’s plane approached, with the first warning coming near Nanxun Reef, accusing the tiny propeller plane of being a “military aircraft”.
“Unidentified military aircraft in west of Nanxun Reef, this is the Chinese Navy. You are threatening the security of our station! In order to prevent miscalculation leave this area immediately,” it reportedly said.
The plane moved away but further threats came in within 20 nautical miles of Yongshu Island, when another message said it was “threatening security”.
Eventually the aircraft managed to close in on Mischief (Meiji) Reef, which has been transformed by construction since 2012, but further warnings came in over the radio and reportedly continued after pilots stated the plane was a Philippine civilian aircraft en route to Palawan.
Images taken by the BBC showed a huge new runway, ships, military vehicles, troops and continuing land reclamation and building work.
The BBC hired a plane to observe construction on disputed islands in the South China Sea
www.independent.co.uk
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