The U.S. military shot down a suspected Chinese surveillance balloon on Saturday off the coast of South Carolina after it floated for days through U.S. airspace.
Republicans have blasted Biden for the delay in taking down the balloon, however reports have emerged that at least three similar "spy" aircraft were spotted over the U.S. during former President Trump's time in office.
Fox News also reported Sunday that another balloon crashed off the coast of Hawaii late last year.
Here's what we know about the past sightings:
Three sightings during Trump administration
Senior U.S. defense and military officials said Sunday that Chinese balloons similar to the one shot down by the Biden administration flew over the U.S. at least three times while Trump was in the White House.
"PRC government surveillance balloons transited the continental United States briefly at least three times during the prior administration and once that we know of at the beginning of this administration, but never for this duration of time," a Pentagon official said.
President Trump on Sunday denied the claims that the balloons had entered U.S. airspace during his presidency, saying on Truth Social that "China had too much respect for 'TRUMP' for this to have happened."
Trump-era national security adviser John Bolton didn't categorically say the balloons hadn't crossed the U.S., but told Fox News on Sunday that he not aware of any such incidents during his tenure.
Bloomberg reported Sunday, citing a senior administration official, that the U.S. didn't learn about the prior balloon flights until after Trump had left the White House.
It remains unclear exactly when or how Biden administration intelligence officials learned about the past incidents - but they're open to briefing Trump-era officials on the surveillance, according to the report.
Rep. Mike Waltz (R-Fla.) said Sunday that Pentagon officials informed him that "several Chinese balloon incidents have happened in the last few years," including a sighting over Florida.
Balloon sightings were also reportedly noted in the airspace over Texas, Hawaii and the U.S. territory of Guam, according to multiple reports.
CBS News reported that previous balloons were recovered by China after being pushed along by the jet stream.
However, Fox News reported Sunday, citing U.S. officials, that a balloon crashed off the coast of Hawaii four months ago, though it did not say whether it was recovered.
Sen. Marco Rubio (R-Fla.) on Sunday acknowledged that aircraft have been spotted before, but said the length of the latest flight means there's "no comparison" to prior sightings.
"That it flew briefly over some part of the continental U.S., that's one thing, but what we saw this week, it's unprecedented and that's why everyone's reacting the way they're reacting," Rubio said.
Balloon downed by Biden has 'intelligence value' for U.S.
The balloon shot down off South Carolina's coast could help the U.S. understand what China is trying to do with the balloons.
China has claimed the balloon downed over the weekend is a weather balloon that was blown unwillingly into American airspace - a claim the U.S. says is refuted by the recovered aircraft wreckage.
"This was a PRC surveillance balloon. This surveillance balloon purposefully traversed the United States and Canada. And we are confident it was seeking to monitor sensitive military sites," a top defense official said Sunday.
"We have learned technical things about this balloon and its surveillance capabilities. And I suspect if we are successful in recovering aspects of the debris, we will learn even more," the official added.
Senators are set to be briefed on the downed balloon next week.
Additional balloons spotted in Central and South America
The balloon shot down in South Carolina this weekend isn't the only such aircraft operating in the Western Hemisphere, Pentagon officials said Sunday.
Officials have seen at least one other Chinese surveillance balloon floating over Central and South America - and additional balloons have been spotted over several countries in the past few years, in Europe and Asia.
"These balloons are all part of a PRC fleet of balloons developed to conduct surveillance operations, which have also violated the sovereignty of other countries," officials said.
Updated: 10:02 p.m.
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