US Demands Return of Seized Drone by Chinese Navy in South China Sea

— -- A U.S. oceanographic underwater drone was seized by a Chinese Navy warship in international waters of the South China Sea on Thursday. The United States has filed a diplomatic protest with China over the incident, demanding the return of the drone that was clearly marked as U.S. government property.

The incident occurred Thursday afternoon local time about 50 nautical miles northwest of Subic Bay in the Philippines as the USNS Bowditch, a civilian-manned U.S. Navy oceanographic vessel, was conducting research using an unmanned underwater vehicle (UUV) known as an "Ocean Glider." The UUV was "gathering military oceanographic data such as salinity, water temperature and sound speed ... in accordance with international law," a Pentagon spokesman said.

The crew of the Bowditch was in the process of recovering one of the two ocean gliders when a small boat was launched from a nearby Chinese Navy warship. The small boat retrieved the other drone from the water and returned it to the Chinese vessel.

The American crew contacted the Chinese vessel by radio multiple times, demanding the return of the drone. The demands were ignored, the Pentagon said.

The only response the Chinese vessel gave was "we are returning to normal operations" as it pulled away from the Bowditch, according to the Pentagon.

"Using appropriate government-to-government channels, the Department of Defense has called upon China to immediately return an unmanned underwater vehicle (UUV) that China unlawfully seized on Dec. 15 in the South China Sea while it was being recovered by a U.S. Navy oceanographic survey ship," said Peter Cook, the Pentagon press secretary, in a statement released Friday.

"The UUV is a sovereign immune vessel of the United States," said Cook. "We call upon China to return our UUV immediately, and to comply with all of its obligations under international law."

A U.S. defense official said there was no indication as to why the Chinese would want to pick up an unclassified drone used for ocean research.

The South China Sea has become an international focal point for China, the United States and other countries in the region.

China has claimed seven reefs in the Spratly Island chain as its own, essentially dredging them into islands. There are also territorial claims over the Paracel Islands located east of Vietnam and the Scarborough Shoal, 200 miles west of the Philippines.

New satellite imagery released publicly by a Washington think-tank this week seem to indicate that China has begun placing "significant" military defenses on the artificial islands it has built up in the Spratly Islands.