It was like somebody punched a hole in the sky

Some said they were interviewed by United officials and instructed to write reports and draw pictures of what they observed, and that they were advised by United officials to refrain from speaking about what they saw.

Like United, the FAA originally told the Tribune that it had no information on the alleged UFO sighting. But the federal agency quickly reversed its position after the newspaper filed a Freedom of Information Act request.

All the witnesses to the O'Hare event, who included at least several pilots, said they are certain based on the disc's appearance and flight characteristics that it was not an airplane, helicopter, weather balloon or any other craft known to man.

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