TAIPING ISLAND, SOUTH CHINA SEA — Taiwan’s Ministry of Defense would like to keep its military facilities in the South China Sea secret, and is asking Google to blur satellite images of the area on its Earth and Map services.

China Post reports that new military construction was recently revealed on Taiwanese-controlled Taiping, the largest naturally occurring feature in the much-disputed Spratly Islands.

Eagle-eyed observers spotted four three-pronged concrete structures arranged in a semicircle near the northwest shoreline. Defense officials aren’t disclosing what they are, but experts speculate that they could be anti-aircraft towers.

Taiping, also known as Itu Aba, already has a 1,195-meter airstrip that’s long enough to accommodate F-16 fighter jets, C-130 Hercules cargo planes, and P-3C patrol crafts, according to the Asia Maritime Transparency Initiative. With these aircraft, surveillance patrols have an operational radius of up to 2,500 kilometers.

A pier completed earlier this year on Taiping has a 210-meter berth, capable of docking 10,000-tonne frigates, reports the Taipei Times.

Taiping has other existing installations, including a command post, radar, and lighthouse. It is classified as a rock and not an island under the UN Convention on the Law of the Sea, a ruling which Taiwan strongly rejects.