Cops Say Chikezie Used Hot Credit Card

Chikezie Eze was arrested after trying to buy men's cologne on a stolen credit card ... law enforcement sources tell TMZ.

We broke the story ... the former "American Idol" was busted at Neiman Marcus last night and booked on felony identity theft.

Chikezie told us earlier today he used a Neiman's credit card with his name on it to purchase two bottles of cologne, but we've now learned the store flagged the plastic as a "stolen credit card."

Chikezie is out on $50,000 bail ... the approximate price of two bottles of cologne at Neiman's.

UPDATE: A rep for Neiman Marcus tells TMZ, "We're cooperating with local authorities."