The Chicago Bears' game against the Baltimore Ravens is being delayed because of heavy rain and wind.
Play was stopped with just under five minutes left in the first quarter with the Ravens leading 10-0 on Sunday. Baltimore's Justin Tucker had just kicked a 52-yard field goal when fans were ordered to seek cover.
Players stayed on the sideline for a few minutes before heading to the locker room.
There are reports of at least one tornado touching down in Illinois and extensive damage in at least one part of the state.