A tourist spotted the errant alligator under an airport sign . Walker told CNN affiliate WBBM-TV . An airport worker used a brush and brush to capture the 18-inch specimen . Twitter photos show an alligator on the Blue Line train to Chicago .
A tourist spotted the errant alligator under an airport sign . An airport worker used a brush and brush to capture the 18-inch specimen . Twitter photos show an alligator on the Blue Line train to Chicago .