Photo credits to CSIS/AMTI

A U.S. think tank said Friday, that China has nearly completed two other runways on their artificial islands in the disputed South China Sea (West Philippine Sea), and that China appears to be speeding up its constructions to claim sovereignty in the area.

The Center for Strategic and International Studies (CSIS), revealed the findings after China’s recent series of test flight on the Fiery Cross Reef in Spratly Islands.

U.S. believes that China has built or building airstrips on its at least three man-made islands where China is in dispute with other claimants such as the Philippines and Vietnam.

Satellite Imagery of Subi Reef’s runway nearing completion, photo credit to CSIS/AMTI

In addition to an airstrip in Fiery Cross Reef, China’s Construction of an airstrip with a 3,250-meter runway on Subi Reef and a 2,644-meter runway on Mischief Reef is nearing completion, according to CSIS.

See also: ‘US won’t allow China to control West Philippine Sea’

Satellite imagery of Mischief Reef’s runway nearing completion, photo credits to CSIS?AMTI

Mischief Reef lies within the Exclusive Economic Zone (EEZ) of the Philippines. It’s just 21 nautical miles from a World War II-era tank landing ship, the BRP Sierra Madre which intentionally grounded by the Philippines in 1999. The airfield would also be just 60 nautical miles from Reed Bank, where the Philippines hopes to drill for natural deposits over China’s objections.

Satellite imagery of Fiery Cross Reef, photo credits to CSIS/AMTI

See also: 6 Possible Philippine bases to be used by US Armed Forces

The airstrip on Fiery Cross Reef where China did the test flights, took at least seven months to finished, but “at Mischief, where grading began in September or October, construction is already approaching completion just three to four months later,” CSIS said.

Under a U.N. convention, no territorial claim can be recognized to artificial islands built on submerged reefs, the United States said.

All three reefs located in the Spratly were submerged before China began its massive reclamation.

The U.S. has urged China to refrain from any acts that could raise tension in the area. -John Esconde

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