Washington: The United States has not yet been able to identify recently downed objects found in North American airspace, White House national security spokesman John Kirby said on Monday.
Kirby told a White House press briefing that closer scrutiny of airspace may partially explain the increase in objects detected but that they were not assessed as a threat to people on the ground and showed no signs they had maneuvering or propulsion capability.
US military fighter jets on Sunday shot down an octagonal object over Lake Huron, the Pentagon said, the latest incident since a suspected Chinese surveillance balloon put North American security forces on high alert.
Kirby added that the United States was not flying balloons over China and that he was not aware of any other US craft flying into Chinese airspace.
Searching for debris
The search for debris from the three objects continued Monday. In Canada's Yukon province, Prime Minister Justin Trudeau said he toured with some Canadian forces who will be leading recovery efforts on the ground.
Heavy snow was making conditions hazardous for the recovery efforts in what Trudeau said was a "fairly large area" between Dawson City and Mayo in central Yukon.
The search is in "a stretch of terrain that is extremely challenging and difficult to access," Public Safety Minister Marco Mendicino told reporters in Ottawa.
"This is a very serious situation that we are taking incredibly seriously," Trudeau said, adding that he would speak to Biden fact-to-face about the objects in March, when the US president is expected to make a visit to Canada.
A Canadian coast guard ship and two coast guard helicopters were helping the search and recovery in Lake Huron, said Joyce Murray, the minister of fisheries and oceans.