"A remote controlled aircraft, or what? Something just went by the other way ... About 20 to 30 seconds ago. It was like a large remote-controlled aircraft."
The Federal Aviation Administration is investigating a mysterious flying object that nearly caused a mid-air collision Monday evening over Denver, according to NBC affiliate KUSA.com.
The FAA says it has reviewed radar and audio recordings from the reported incident and hasn't found what it calls unidentified targets.
Investigators believe the object, whatever it is, could pose a serious safety hazard to planes.
Read more: MSNBC