US intelligence sources insisted on Tuesday that the balloon shot down on Saturday was used by the Chinese military for spying.
Unnamed officials told the Washington Post they believed such balloons were used to collect intelligence on strategically relevant territories. They include Japan, India, Taiwan and the Philippines.
Chinese officials have already denied using such balloons for surveillance. China maintains the vessel was a weather balloon thrown off course.
An official told the Washington Post that the US intelligence community believed some of the balloons were being flown from Hainan, a southern Chinese island that is home to a naval military base.
Quoting an unnamed senior Biden administration official, CBS News confirmed that the US intelligence community believed the balloon was part, in its words, of an “aerial surveillance program run by the People’s Liberation Army out of Hainan”.
The US does not know the precise size of the fleet of Chinese surveillance balloons, but sources told CNN that the program has conducted at least two dozen missions over at least five continents in recent years.
Roughly half a dozen of those flights have been within US airspace – although not necessarily over US territory, according to one official familiar with the intelligence.
And not all of the balloons sighted around the globe have been exactly the same model as the one shot down off the coast of South Carolina on Saturday, that official and another source familiar with the intelligence said. Rather, there are multiple “variations,” these people told CNN.
US briefs allies on Chinese balloon
On Monday, the US briefed 40 allied countries about the alleged espionage, a senior Biden administration official confirmed to CBS News.
In that briefing, Deputy Secretary of State Wendy Sherman also revealed one balloon had circumnavigated the planet in 2019, traveling over Hawaii and Florida.
CNN reports that an elite team of FBI engineers is poring over the remnants of the recovered balloon, trying to learn everything it can about the intelligence it may have gathered and how best to track surveillance balloons in the future.
Sources familiar with the effort say that officials want to understand as much as possible about the balloon’s technical capabilities including what kind of data it could intercept and gather, what satellites it was linked to and whether it has any vulnerabilities that the US might be able to exploit.
And perhaps critically, the investigators will be looking at what digital signatures it emitted to see if they provide a better way for the US to track this kind of balloon in the future.