Several U.S. Navy and Coast Guard vessels established a security perimeter where the balloon hit the water, about six nautical miles off the coast of South Carolina, and were searching for debris, a senior defense official and a senior military official said on Feb. 4.

"The nature of the debris is still being assessed. But recovery options will seek to recover all debris and any material of intelligence value," the defense official said. "And we'll make sure that we're working closely with the FBI on the chain of custody as we do so."

The two officials didn't give an estimate of how long the recovery will last but noted that the mission should be "fairly easy," since the balloon came down in a shallow area.

The recovery of the balloon will allow analysts to examine any sensitive Chinese equipment, according to the defense official.

"I would also note that while we took all necessary steps to protect against the PRC surveillance balloon's collection of sensitive information, the surveillance balloon's overflight of U.S. territory was of intelligence value to us," the defense official said, using the acronym for the People's Republic of China.

"I can't go into more detail, but we were able to study and scrutinize the balloon and its equipment, which has been valuable."

Navy divers and a salvage vessel under U.S. Northern Command will join the recovery effort, the military official noted.