U.S. officials claimed on Thursday that a suspected Chinese spy balloon had been flying over the country for a few days. This would be a daring gesture only days before U.S. Secretary of State Antony Blinken is scheduled to visit Beijing.

Fighter planes were activated, but military officials warned President Joe Biden against firing the balloon out of the sky out of concern that flying debris could endanger his safety. Biden heeded their advice, according to U.S. sources.

One of the sources told reporters under the condition of anonymity that the United States had taken "custody" of the balloon when it entered American territory and had been watching it with manned military planes.

In light of escalating tensions between the superpowers, the event serves as a reminder of the extent Beijing and Washington have been prepared to go in order to spy on one another.

According to Pentagon spokesman Brigadier General Patrick Ryder, "The United States government has spotted and is following a high-altitude surveillance balloon that is now over the continental United States."

The balloon is now flying at a height much above commercial air traffic, and neither a military threat nor a physical danger to anyone on the ground exists.

In accordance with a visit that Biden and Chinese President Xi Jinping agreed to in November, Blinken is anticipated to depart for China the following week. It was unclear how the spy balloon's discovery may affect such plans.

An inquiry for comment from Reuters was not immediately answered by the Chinese foreign ministry.

Through diplomatic channels in Beijing and Washington, U.S. officials discussed the matter with their Chinese counterparts. According to a U.S. official, "We have expressed to them the seriousness with which we take this matter."

The spy balloon, according to U.S. Senator Marco Rubio, the top Republican on the Senate intelligence committee, is troubling but not unexpected.

Rubio wrote on Twitter, "Beijing's degree of espionage aimed at our country has grown considerably more intense & blatant over the previous 5 years.

Senator Tom Cotton, a fellow Republican, urged Blinken to postpone his journey.

In reference to a classified national security briefing for congressional leaders and the Republican and Democratic leaders of the intelligence committees, Republican House Speaker Kevin McCarthy indicated he will ask for a "Gang of Eight" briefing. A U.S. official stated that the Biden administration briefed Gang of Eight officials earlier on Thursday and has offered more briefings.

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In particular, after then-U.S. House Speaker Nancy Pelosi's travel to Taiwan in August, which sparked major Chinese military drills close to the self-governing island, relations between China and the United States have deteriorated recently.

Since then, Washington and Beijing have worked to increase communication and stop relations from deteriorating.

POSSIBLE RISK TO SAFETY

According to the insider, American military officials debated shooting down the balloon over Montana on Wednesday but ultimately counseled Biden against it due to the danger posed by falling debris.

The military deployed resources, including F-22 fighter jets in case Biden ordered the balloon to be shot down, and the airport in Billings, Montana, issued a ground stop.

The official said, "We wanted to make sure we were working with civil authorities to clear the airspace over that prospective location.

"However, despite taking these safety precautions, our military commanders believed that we hadn't lowered the risk to an acceptable level. We decided not to attempt the shot."

Without providing further information, the official stated that the balloon would pass over several sensitive locations on its current flight path. 150 intercontinental ballistic missile silos are located at the Montanan Malmstrom Air Force Base.

Before entering the country, the surveillance balloon was tracked near the Aleutian Islands and Canada, according to a different U.S. official.

Officials would not specify the balloon's altitude, although they did admit that it was operating above commercial air travel and below "space."