The Pentagon on Friday said it detected another Chinese surveillance balloon - this one transiting Latin America, which comes a day after the US identified the first one over Montana.
Beijing said the balloon over the US is a civilian airship intended for scientific research, however, Secretary of State Antony Blinken scrapped a high profile visit to China over the incident.
"It is hard to imagine why the Chinese would risk sending military-grade surveillance equipment in a vulnerable, uncontrollable balloon that cannot even be directed to a specific target," former Pentagon analyst Chuck Spinney said. "These high altitude balloons basically go with the wind-flows."
US constitutional historian and political commentator Dan Lazare said the US response has been a gross overreaction. Canceling an important diplomatic trip over something as trivial as this is absurd, he added.
China's foreign ministry on Friday said the airship deviated far from its planned course and regrets the unintended entry into US airspace due to force majeure.