This marks the fourth unidentified flying object that has been destroyed over North America this month. US officials identified the first object as a Chinese surveillance balloon,and the detection has strained US relations with Beijing.

The incident raised questions about the spate of unusual objects that have appeared over North American skies in recent weeks and raised tensions with China.

“We need the facts about where they are originating from,what their purpose is,and why their frequency is increasing,” said US representative Debbie Dingell,one of several Michigan legislators who applauded the military for downing the object.

The first object was a balloon shot down off the coast of South Carolina on February 4. On Friday,a second object was shot down over sea ice near Deadhorse,Alaska. A third object was destroyed over Canada’s Yukon on Saturday,with investigators still hunting for the wreckage.

“Recovery teams are on the ground,looking to find and analyse the object,” Prime Minister Justin Trudeau told reporters on Sunday.

“The security of citizens is our top priority and that’s why I made the decision to have that unidentified object shot down,” he said,adding that it had posed a danger to civilian aircraft.

North America has been on high alert for aerial intrusions following the appearance of a white,eye-catching Chinese airship over American skies earlier this month.

That 200-foot-tall (60-metre) balloon – which Americans have accused Beijing of using to spy on the United States – caused an international incident,leading Secretary of State Antony Blinken to call off a planned trip to China only hours before he was set to depart.

Surveillance fears appear to have US officials on high alert. Twice in 24 hours,US officials closed airspace – only to reopen it swiftly.

On Sunday,the Federal Aviation Administration briefly closed space above Lake Michigan. On Saturday,the US military scrambled fighter jets in Montana to investigate a radar anomaly there.

China denies the first balloon was being used for surveillance and says it was a civilian research craft. It condemned the United States for shooting it down off the coast of South Carolina last Saturday.

Reuters

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