Prime Minister Justin Trudeau said on Saturday that on his order a US plane shot down an unidentified object that was flying high over northern Canada, a day after similar action over Alaska.
Shortly before Mr Trudeau’s tweet, the North American Aerospace Defence Command said it had detected the object.
The object was the third known to have violated North American airspace in the past two weeks.
In a second tweet, Mr Trudeau said: “I spoke with President Biden this afternoon. Canadian forces will now recover and analyse the wreckage of the object. Thank you to Norad for keeping the watch over North America.”
Spokesman Maj Olivier Gallant said both Canadian and US jets operating as part of Norad had been deployed.
US fighter jets from Joint Base Elmendorf-Richardson, Alaska, monitored the object as it crossed over into Canadian airspace, where Canadian CF-18 and CP-140 aircraft joined the formation.
“A US F-22 shot down the object in Canadian territory, using an AIM 9X missile following close co-ordination between US and Canadian authorities,” Pentagon spokesman Brig Gen Patrick Ryder said.
Canadian Defence Minister Anita Anand declined to speculate about the origin of the object, which she said was cylindrical in shape.
She stopped short of calling it a balloon but said it was smaller than the Chinese balloon shot down off South Carolina's coast a week ago, though similar in appearance.
“There is no reason to believe that the impact of the object in Canadian territory is of any public concern,” Ms Anand said.
F-22 jets have now downed three objects in the airspace above the US and Canada over seven days, raising questions on what is hovering overhead and who has sent them.
At least one of the objects downed was believed to be a spy balloon from China, but the other two have not yet been identified.
The downing came a day after White House National Security Council spokesman John Kirby said an object roughly the size of a small car was shot down in remote Alaska.
Officials couldn’t say if it contained any surveillance equipment, where it came from or what purpose it had.
Mr Kirby said it was shot down because it was flying at about 40,000 feet (13,000 metres) and posed a “reasonable threat” to the safety of civilian flights, not because of any knowledge that it was engaged in surveillance.
US Northern Command said recovery operations continued Saturday on sea ice near Deadhorse, Alaska.
It said there were no new details on what the object was. Alaska Command and the Alaska National Guard, along with the FBI and local law enforcement, were conducting search and recovery, it added.
“Arctic weather conditions, including wind chill, snow and limited daylight, are a factor in this operation, and personnel will adjust recovery operations to maintain safety,” it said.
The joint US-Canadian operation comes after several Republicans criticised Mr Biden for not shooting down the Chinese balloon sooner. The US military had recommended waiting until it was over the sea, for fear of injuries from falling debris.
The US Navy has been scouring the sea to recover debris and the undercarriage of electronic gadgetry since the shootdown of the 60-metre-tall Chinese balloon.
The Pentagon has said a significant amount of the balloon had already been recovered or located, suggesting American officials may soon have more information about any Chinese espionage capabilities aboard.
Sea conditions on February 10 “permitted dive and underwater unmanned vehicle activities and the retrieval of additional debris from the sea floor,” Northern Command said.
“The public may see US Navy vessels moving to and from the site as they conduct offload and resupply activities,” it said.