Subi Reef is shown in this handout satellite image dated September 3, 2015 and provided by CSIS Asia Maritime Transparency Initiative/Digital Globe September 14, 2015. China's apparent construction of a third airstrip on its man-made islands in the disputed South China Sea could fill a gap in Beijing's anti-submarine defenses, complicating operations for the U.S. Navy and its allies, Chinese and Western experts said. Satellite photographs show construction is almost finished on a 3,000-meter-long (10,000-foot) airstrip on Fiery Cross Reef. Recent images showed Subi Reef would also have a 3,000-meter airstrip, Greg Poling, director of the Asia Maritime Transparency Initiative at the Center for Strategic and International Studies think tank in Washington, said on Monday. Poling, citing images taken last week, said China also appeared to be doing preparatory work for an airstrip on Mischief Reef. To match story SOUTHCHINASEA-CHINA/SUBMARINESREUTERS/CSIS Asia Maritime Transparency Initiative/Digital Globe/Handout via Reuters ATTENTION EDITORS - THIS PICTURE WAS PROVIDED BY A THIRD PARTY. REUTERS IS UNABLE TO INDEPENDENTLY VERIFY THE AUTHENTICITY, CONTENT, LOCATION OR DATE OF THIS IMAGE. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS. EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. NO SALES. NO COMMERCIAL USE.
