The plane was flying over Arizona on the way from San Diego to Dallas.
An FAA spokesperson said the agency is not sure what flew over both planes, but it may not be something extraterrestrial.
The spokesperson said that there are high-altitude weather balloons and other aircraft that operate in that area but the controller was not able to pinpoint aircraft at the time, CNN reported.
The controller said the pilot described the unidentified flying object as having “a big reflection” and “was traveling several thousand feet above us, going the opposite direction.”
The sighting happened near Roswell, New Mexico, the site where, what many believe, was a UFO crashed in 1947. The government said it wasn't a UFO back then, either; it claimed it was a weather balloon, CNN reported.
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