WASHINGTON 

The Pentagon is tracking a suspected Chinese high-altitude surveillance balloon over the continental US, an official said Thursday.

“We continue to track and monitor it closely," Pentagon spokesman Brig. Gen. Pat Ryder told reporters.

“The balloon is currently traveling at an altitude well above commercial air traffic and does not present a military or physical threat to people on the ground,” he added.

"Once the balloon was detected, the US government acted immediately to protect against the collection of sensitive information," said Ryder, noting that similar activity had been previously observed over the past several years.

A senior defense official said the balloon was "clearly" intended for surveillance and entered US airspace a couple of days ago.

“We had been looking at whether there was an option yesterday” to take down the balloon “over some sparsely populated areas in Montana, but we just couldn't buy down the risk enough to feel comfortable recommending shooting it down yesterday,” the official added.

President Joe Biden was briefed about the balloon and asked for military options, according to the official.

"Currently, we assess that this balloon has limited additive value from an intelligence collection perspective. But we are taking steps nevertheless to protect against foreign intelligence collection of sensitive information," the official added.