cannot see robbers

[dubesor]

I am unable to see robbers. I have never caught a robber. When the message pops up about robber in the airport I literally pause and scan the entire airport pixel by pixel, inspecting every single person, and I simply cannot see any robbers! I know what they are supposed to look like but I literally cannot see them! Is this a bug where they become invisible or somehow have a wrong sprite? I literally cannot see them!

[ZephyR]

The guy carrying a red bag is the robber while other normal passengers are carrying a green one. The robber is more likely to stay still and look around in the airport.

[Bishop Hikusaak]

This is taken from the Kairosoft Wiki:
Catching thieves: the thief is *always* a single person (no couples or groups); it walks a short distance before stopping and looking left and right, rinse and repeat; it has no flights to catch and does not have luggage. Successfully catching thieves 3-4 times unlocks the Security Room request — you only need one for the entire airport, and you can then ignore the "reports of suspicious persons" notices thereafter.

[ໂ‧͡‧̫ໃ]

For future reference for anyone else:

You can find the thief when you see a pop up banner on the bottom of your screen mentioning a "suspicious person" in the aiport. Once you see that pop up, search for 1 person with a red backpack.

The important thing is to search only when you see the sus person pop up notification/alert at the bottom of the screen. I wasted so much time searching for them throughout my playthrough 'cos I'm silly.