Experts have been left baffled after strange images emerged of a huge, disc-shaped object over a major city.

On November 7, 2006, an employee at the O’Hare International Airport in Chicago saw a metallic, saucer-shaped UFO flying in the sky.

The reported sighting lasted only five minutes but was witnessed by at least 12 staffers for United Airlines.

At the time, it made international headlines due to a tape released by the Federal Aviation Administration. 

The FAA said the incident was a “hole-punched cloud,” a statement agreed by astronomer Mark Hammergren who was associated with the Alder Planetarium at the time.

However, the case still remains unresolved and has been the subject of much discussion by UFO researchers.

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