China has returned an unmanned underwater vehicle to the U.S. that its navy seized in international waters of the South China Sea last Thursday.
The Pentagon and the Chinese defense ministry confirmed the return of the drone in separate statements issued on Monday night and Tuesday, respectively, with American officials condemning the seizure as unlawful.
"This incident was inconsistent with both international law and standards of professionalism for conduct between navies at sea," Pentagon press secretary Peter Cook said in a statement. "The U.S. has addressed those facts with the Chinese through the appropriate diplomatic and military channels, and have called on Chinese authorities to comply with their obligations under international law and to refrain from further efforts to impede lawful U.S. activities."
The Defense Department said that the United States "will continue to investigate the events surrounding this incident and address any additional findings with the Chinese, as part of our ongoing diplomatic dialogues and the Military Maritime Consultative Agreement Mechanism."
The Pentagon first publicly acknowledged on Friday that a Chinese navy vessel had seized the undersea drone belonging to the USNS Bowditch, a U.S. Navy oceanographic survey ship, when it was conducting routine, unclassified operations in the South China Sea. The incident took place roughly 50 nautical miles northwest of Subic Bay off the coast of the Philippines.
The People's Liberation Army-Navy vessel 510 returned the drone to the USS Mustin near where it was initially seized, the Pentagon said.
As of Monday afternoon, U.S. and Chinese officials were still negotiating the logistics of the drone's return, days after the Chinese defense ministry said that it would return the underwater vehicle and accused the U.S. of dramatizing the incident.
Tensions in the region have risen over China's island-building campaign in the South China Sea, over most which Beijing claims sovereignty. The U.S. Navy has periodically sailed warships close to islands and features claimed by China to demonstrate freedom of navigation, operations that have been met with criticism from Beijing.
The Pentagon emphasized Tuesday that the United States "remains committed to upholding the accepted principles and norms of international law and freedom of navigation and overflight and will continue to fly, sail, and operate in the South China Sea wherever international law allows, in the same way that we operate everywhere else around the world."