( CNN ) -- Carrying an alligator bag on an airline flight is fine , but live alligators are banned from boarding . That might explain why a toothy reptile was slithering around Chicago 's O'Hare International Airport on Friday . Security guard Tineka Walker was on patrol at Terminal 3 when a passenger alerted her to the suspicious object under an escalator . `` I looked , I said , 'What ? ' '' Walker told CNN affiliate WBBM-TV . When Walker radioed for help , Chicago Police Officer Anthony Oliver thought at first it was a crock . `` Figured somebody was messing with us , '' Oliver told WBBM . No need to call Tarzan to wrestle the gator , which was only about 18 inches long . An airport worker used a broom and dustpan to capture it . Animal control picked it up from police and handed it over to the Chicago Herpetological Society . `` What if a little kid grabbed this , thinking it was a toy ? That could do a nasty job , '' said Bob Bavirsha , a reptile rescuer with the group . Legless lizards found at the end of a runway . A major clue to how it ended up at the airport emerged on Twitter on Friday when someone posted photos of a man holding what appeared to be the same alligator . `` The patterns on an alligator are as unique as your fingerprints , '' Bavirsha said . `` We can actually match this band right here with that band right there . '' The man holding the alligator in the tweeted photos also had unusual markings -- a tattoo on his arm that could help investigators identify him . The Twitter posting said the man was riding the Blue Line train , which goes to O'Hare . `` They probably realized they could n't take it through checkpoint , and just let him go , but , oh my God ! '' Walker said . The alligator will eventually find a new life in a reptile park -- after getting a few months of treatment for stunted growth , apparently from not being properly fed . All creatures great and small at Frankfurt Airport 's Animal Lounge .
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 .