An American football game was stopped and fans were evacuated from the stadium due to the threat of severe weather that could pose a "significant risk" to 53 million people in the Midwest.
The game between the Chicago Bears and Baltimore Ravens was "temporarily suspended" in the first quarter with both teams leaving the field and fans told to exit the Soldier Field stadium.
The cancellation of the match in Chicago comes as the US National Weather Service confirmed a tornado hit Peoria, Illinois, and was moving north.
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