Coolio & Entourage: Busted At LAX For Loaded Firearm

4:45 PM PST -- Coolio was just officially booked for possession of a firearm by a felon.

1:55 PM PST -- Cops tell us even though Coolio's bodyguard first claimed possession of the bag, a quick investigation determined other items inside it belonged to Coolio. Cops say the rapper had already boarded a plane and they took him off to join his guard for questioning. We're told Coolio fessed up to owning the bag and it was determined the gun had been stolen. Both were arrested for possession of a stolen loaded firearm.

Coolio and his crew were just cuffed at LAX for allegedly trying to get a loaded firearm through security.

Law enforcement sources tell TMZ the rapper and his team were leaving L.A. Saturday morning when they got flagged by the TSA. We're told a book bag belonging to the group contained a loaded gun. Our sources say a member of Coolio's crew claimed the bag, but witnesses have told cops it was Coolio's.

Cops are currently reviewing video footage and taking witness statements to sort out who owns the gun and bag.

A rep for Coolio tells us the gun belongs to the rapper's security guard but he's been detained for questioning and will be fully cooperative.

At this time, it's unclear what type of gun was found.

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