The United States on Saturday shot down a giant Chinese balloon it claims had been spying on key military locations across the country.

In a statement, Secretary of Defense Lloyd Austin said that an F-22, supported by other fighter jets, successfully brought down the high-altitude Chinese surveillance balloon in skies over the coast of South Carolina upon orders from President Joe Biden.

The balloon, with a size approximately equivalent to three buses, was seen falling into the sea after a small explosion. The U.S. Navy has begun to recover the debris to investigate whether the balloon had data-collecting equipment.

Beijing, for its part, has protested what it called Washington's excessive response, contending that the balloon was not a spying aircraft but a civilian craft that had entered U.S. airspace by accident.

U.S. defense officials earlier announced that the balloon was initially detected near Alaska's Aleutian Islands on January 28 before traveling north into Canadian airspace and then re-entering the U.S. last Tuesday.

On Wednesday, it was spotted over the state of Montana, where a number of sensitive U.S. nuclear missile sites are located.