Rae Sremmurd -- No Skate Zone at LAX Baggage Claim

The guys of Rae Sremmurd are 19 and 21 years old, but they act like they're 12 ... as evidenced by the hijinks they got into while waiting for their bags at LAX ... which even got them into trouble with airport security.

The "No Flex Zone" rappers (Swae Lee and Slim Jimmy) looked like kids who escaped their mother ... as one rode a skateboard and the other rode the baggage carousel. It was just good-natured fun, but one security guard actually got on the loudspeaker to calm them down!

When it came time to finally chat with our photog, the fellas claimed their music is capable of raising the dead ... literally!