The United States on Friday demanded that China should "immediately" release the American underwater naval drone "unlawfully" seized by the mainland in international waters in the South China Sea.
The incident hit a new point of tension between the US and Chinese military forces in the disputed waters. Pentagon Press Secretary Peter Cook said that China must comply with all of its obligations under international law and return the drone taken by it.
"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 December 15 in the South China Sea while it was being recovered by a US Navy oceanographic survey ship," Cook said.
The South China Sea dispute involves island and maritime claims in the region among several sovereign states around the area, including the People's Republic of China, the Republic of China (Taiwan), Malaysia, the Republic of the Philippines, the Nation of Brunei and the Socialist Republic of Vietnam. Many international non-claimant nations, however, want the South China Sea to remain as international waters considering a high proportion of world's trade passes through the region. The US also conducts operations around the sea to oversee the "freedom of navigation" in the region.
Cook also added that the USNS Bowditch (T-AGS 62) and the UUV system is used around the world to assimilate military oceanographic information like salinity, water temperature, and sound speed. He said that the UUV system was conducting routine operations in accordance with the international law around 50 nautical miles northwest of Subic Bay, Philippines, when a Chinese Navy PRC DALANG III-Class ship (ASR-510) launched a small boat and retrieved the UUV.
"Bowditch made contact with the PRC Navy ship via bridge-to-bridge radio to request the return of the UUV. The radio contact was acknowledged by the PRC Navy ship, but the request was ignored. The UUV is a sovereign immune vessel of the US. We call upon China to return our UUV immediately, and to comply with all of its obligations under international law," Cook said.
A US think tank on Thursday had cited satellite images to say that China has installed new weapon systems, including anti-aircraft and anti-missile systems, on the artificial islands in the South China Sea. China had earlier claimed that it did not intend to militarise the region which falls on a strategic trade route.
A Ranking Member of the Senate Foreign Relations Committee, Senator Ben Cardin, said that China's seizure of the unmanned scientific research submersible in international waters is an outright violation of international law.
"No matter its motivation, China needs to explain its actions and immediately return the undersea drone, untampered with, to the United States," he said.
