Manila: The presence of new structures in a disputed area in the South China Sea has raised security concerns for the Philippines, although an official said they are still verifying if the new objects are indeed weapons.

According to Asia Maritime Transparency Initiative (AMTI), a think tank, a number of buildings have been constructed by China on three islands, namely Fiery Cross, the Mischief Reef and Subi Reef, which are located halfway between the Philippines and Vietnam in the South China Sea.

“We are verifying. If it is true it is a big concern for us and the international community,” Philippine Department of National Defence Secretary Delfin Lorenzana said in reports.

The Philippine official added the area where the structures are located lies along international sea lanes. used by commercial shipping vessels.

According to AMTI, China has built structures capable of holding defensive weapons such as large anti-aircraft guns and rapid fire arms that could take out low flying aircraft or even cruise missiles.

“AMTI began tracking the construction of identical hexagon-shaped structures at Fiery Cross, Mischief Reef and Subi Reefs in June and July. It now seems that the structures are an evolution of point defence fortifications already constructed at China’s smaller facilities on Gaven, Huges, Johnson and Cuarteron Reefs,” it said.

China already maintains four airbases and airports in the Spratlys, particularly in Yongshu, Subi and Mischief, in addition to Taiping island.

The presence of these structures has greatly upset the balance of power in the South China Sea.

Earlier, the Philippines brought the issue of conflicting sea territory claims with China before the UN Arbitration Court. The tribunal’s decision largely favoured Manila, but Beijing stood pat on its claim that most of the South China Sea are theirs by virtue of historic rights.

China had earlier built radar facilities in the disputed reefs which improved its air force’s capability to detect approaching aircraft.