TMZ has learned Naomi Campbell has been arrested at Heathrow Airport after she allegedly assaulted a police officer. Why? Bitch lost her bag!!

Campbell was pulled off a British Airlines flight this morning after reportedly causing a huge stink as one of her -- count 'em -- three carry-on bags had gone missing. The Sun says after she was yanked off the plane, cops had to be called because the supermodel was told she was unfit to fly. The anger management class superstar was hauled away "ranting and raving" from BA's first class lounge after allegedly assaulting an officer.

Witnesses say they heard the model scream "get off me, leave me alone" as she was taken to the Heathrow police station. Hide your Blackberries!

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