US President Joe Biden ordered a fighter jet to shoot down an unidentified high-altitude object off Alaska on Friday.
The White House Spokesman John Kirby said the unmanned object was the size of a small car and posed a “reasonable threat” to civilian aviation.
Mr Kirby said the object’s purpose and origin was unclear.
It comes a week after the American military destroyed a Chinese balloon over US territorial waters.
Speaking at the White House on Friday, Mr Kirby said the debris field of the object shot down on Friday was “much, much smaller” than the balloon shot down last Saturday off the coast of South Carolina.
He said that the object was flying at 40,000ft (12,000m) over the northern coast of Alaska.
It had already flown across Alaska at a speed of 20 to 40mph (64km/h) and was out over the sea travelling towards the North Pole, when it was shot down.
BBC reports that the object was first spotted on Thursday night, though officials did not specify a time.
Writing by Chinasa Ossai; Editing by Adeniyi Bakare