The airspace over Lake Michigan in the northern US was closed on Sunday for “national defense” reasons, the US Civil Aviation Regulatory Authority (FAA) announced on Sunday.

The Great Lakes of North AmericaPhoto: NASA Earth / Zuma Press / Profimedia

The announcement came after at least three flying objects, including what Washington called a Chinese spy balloon, were shot down in one week over the United States and Canada.

On Saturday, the airspace over the US state of Montana was temporarily closed, but a fighter jet sent to investigate a “radar anomaly” did not detect any flying “object”, the US military said.

On Sunday, news agencies reported that China is also preparing to shoot down an unidentified object in its airspace, and Canada is conducting a ground search for a cylindrical flying object shot down by American Air. Power.