Pentagon officials have refused to rule out an alien origin for the latest object that was spotted floating in US airspace and was shot down Sunday.
On orders from President Joe Biden, a US fighter jet shot down an “unidentified object” over Lake Huron, near the border with Canada.
It was the fourth such downing in eight days and follows accusations from the US military against China of an extended surveillance operation.
Remains of the three latest objects shot down are being analysed, and their origin has not been determined yet, with an official refusing to rule out that this might be extra-terrestrial.
When asked on Sunday, General Glen VanHerck, who is in charge of North American Aerospace Defense Command and Northern Command, said: "I'll let the intel community and the counterintelligence community figure that out. I haven't ruled out anything.
"At this point, we continue to assess every threat or potential threat, unknown, that approaches North America with an attempt to identify it."
However, After the general’s remarks, a Defence official who requested anonymity to speak about a developing situation said that there is “no indication of aliens or extraterrestrial activity with these recent takedowns.”
The Pentagon officials said they were still trying to determine what exactly the objects were and said they had considered using the jets' guns instead of missiles, but it proved to be too difficult.
They drew a strong distinction between the three shot down over this weekend and the balloon from China.
The extraordinary air defence activity began in late January, when a white orb the officials said was from China appeared over the US and hovered above the nation for days before fighter jets downed it off the coast of Myrtle Beach, South Carolina.
That event played out over livestream. Many Americans have been captivated by the drama playing out in the skies as fighter jets scramble to shoot down objects.
Since then, fighter jets last week also shot down objects over Canada and Alaska. Pentagon officials said they posed no security threats, but so little was known about them that Pentagon officials were ruling nothing out — not even UFOs.
“We have been more closely scrutinizing our airspace at these altitudes, including enhancing our radar, which may at least partly explain the increase,” said Melissa Dalton, assistant defence secretary for homeland defence.
US and Canadian authorities had restricted some airspace over the lake earlier Sunday as planes were scrambled to intercept and try to identify the latest object.
According to a senior administration official, the object was octagonal, with strings hanging off, but had no discernable payload.
It was flying low at about 20,000 feet, the official who spoke to the AP on condition of anonymity.
US officials were still trying to precisely identify two other objects shot down by F-22 fighter jets and were working to determine whether China was responsible as concerns escalated about what Washington said was Beijing's large-scale aerial surveillance program.
Meanwhile, China said more than 10 US high-altitude balloons have flown in its airspace during the past year without its permission, following Washington's accusation that Beijing operates a fleet of surveillance balloons around the world.
The Chinese allegation comes after the US shot down a suspected Chinese spy balloon that had crossed from Alaska to South Carolina, sparking a new crisis in bilateral relations that have spiralled to their lowest level in decades.
Foreign Ministry spokesperson Wang Wenbin gave no details about the alleged US balloons, how they had been dealt with or whether they had government or military links.
“It is also common for US balloons to illegally enter the airspace of other countries," Wang said at a daily briefing. “Since last year, US high-altitude balloons have illegally flown over China’s airspace more than 10 times without the approval of Chinese authorities."
Wang said the US should “first reflect on itself and change course, rather than smear and instigate a confrontation."
China says the balloon shot down by the US was an unmanned airship made for meteorological research that had been blown off course. It has accused the US of overreacting by shooting it down and threatened to take unspecified action in response.
