The Chicago Bears' game against the Baltimore Ravens has resumed after being delayed about two hours because of a torrential downpour.
Play was stopped with 4:51 left in the first quarter. Baltimore's Justin Tucker had just kicked a 52-yard field goal to make it 10-0 when fans were ordered to seek cover.
Players stayed on the sideline for a few minutes before heading to the locker room as heavy rains and strong winds hit.
There were reports of at least one tornado touching down in Illinois and extensive damage in parts of the state. At Soldier Field, long lines formed in the upper deck as drenched fans tried to make their way toward the tunnel with lightning striking near the stadium.