The US military on Sunday shot down an unidentified flying object above Lake Huron, near the border with Canada.

“The object has been downed by pilots from the US Air Force and National Guard,” said Representative Elissa Slotkin of Michigan, which lies south of the lake.

It is the third unidentified object to be shot down by American fighter jets in as many days.

This follows a week-long Chinese “spy balloon” saga that has intensified the hunt for violations of airspace above North America.

On Saturday, US fighter jets shot down an object flying over Yukon near the US border with Canada, after shooting down another flying object a day before near Deadhorse, Alaska.

“These objects did not closely resemble and were much smaller than the PRC balloon and we will not definitively characterize them until we can recover the debris, which we are working on,” the Reuters news agency quoted the spokesperson as saying.

Canadian Prime Minister Justin Trudeau said one of the objects had violated Canadian airspace. He added in a tweet late on Saturday that Canadian forces will recover and analyze the wreckage.

Tension over what the US sees as attempted spying peaked after a massive Chinese balloon was sighted above the US in late January. China insisted the balloon was a “civilian airship used for research,” while the US described it as a “spy balloon” and shot it down.

The Canadian Prime Minister said the unidentified object was brought down by a US F-22, as per his orders.

“Canadian Forces will now recover and analyze the wreckage of the object,” Trudeau said, adding that he was in touch with US President Joe Biden.

Earlier on Sunday, Senate Majority Leader Chuck Schumer told the ABC broadcaster that the shot down objects were balloons, though smaller than the Chinese “spy balloon.”

Schumer said he had been briefed the night before by Biden’s national security advisor, Jake Sullivan. He added that the two objects also flew at a lower altitude of about 40,000 feet (around 12,200 meters).

The surveillance balloon had flown at about 60,000 feet.

The North American Aerospace Defense Command (NORAD) said on Sunday they had temporarily restricted flights over the Lake Michigan area.

The restriction was carried out to “ensure the safety of air traffic in the area during NORAD operations,” it said, without giving details on the nature of the operations.

The measure has since been lifted.

The sight of the Chinese balloon drifting over the US prompted to a political uproar in Washington, bringing into focus the challenges China posed to the US and its allies.

Asked during a Pentagon briefing whether he had ruled out an extraterrestrial origin for three airborne objects shot down by U.S. warplanes in as many days, General Glen VanHerck 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,” said VanHerck, head of U.S. North American Aerospace Defense Command (NORAD) and Northern Command.

VanHerck’s comments after a U.S. F-16 fighter jet shot down an octagonal-shaped object over Lake Huron on the U.S.-Canada border, acting on orders from U.S. President Joe Biden.

It was the third unidentified flying object to be knocked out of the sky by U.S. warplanes since Friday, following the Feb. 4 downing of a suspected Chinese surveillance balloon that put North American air defenses on high alert.