"Recovery operations concluded February 16 off the coast of South Carolina, after US Navy assets assigned to US Northern Command successfully located and retrieved debris from the high-altitude PRC surveillance balloon," NORTHCOM said in a statement, referring to the People's Republic of China.

"Final pieces of debris are being transferred to the Federal Bureau of Investigation Laboratory in Virginia for counterintelligence exploitation," it added.

The Chinese balloon traveled across much of the United States before it was shot down over the Atlantic Ocean by a US F-22 Raptor on February 4.

Beijing insisted the device was for weather surveillance and had gone astray, while Washington described it as a sophisticated high-altitude spying vehicle.

Relations between China and the United States have grown increasingly tense over the balloon incident.

Late Friday, NORTHCOM announced in another statement that it was ending searches for two other objects shot down -- one off Alaska's northern coast on February 10 and the other over Lake Huron on February 12.

"The US military, federal agencies, and Canadian partners conducted systematic searches of each area using a variety of capabilities, including airborne imagery and sensors, surface sensors and inspections, and subsurface scans, and did not locate debris," the statement said.

President Joe Biden in a press conference this week about the aerial objects said that preliminary evidence suggested the Alaska and Lake Huron incidents were not related to a broader Chinese spy program.