Oklahoma Tornado LIVE: Moore and Oklahoma City Devastated By Storm

A mile-wide tornado wrecked a path of destruction in Moore, Oklah., on Monday. The tornado  was so big, "it looked like a cloud" on the ground, said some reporters on the scene. A KFOR TV helicopter which was filming the intial tornado flew by the damage after the storm had cleared, showing a scene of complete destruction.

The tornado touched down south of Oklahoma City, perhaps near a casino where people were sheltered, a helicopter pilot for NBC station KFOR reported. 

Watch live reports from the scene here.

Tens of millions of people from Texas to the Great Lakes were warned to brace for severe weather one day after a tornado outbreak killed two elderly men in Oklahoma and turned a trailer park into splinters.

The KFOR television footage showed flattened buildings and fires.

A KFOR TV reporter stated: "This is the most destructive tornado in the history of the world."

There were no immediate reports of injuries.

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