Memo to famous pop stars: cruising can be a dangerous extracurricular activity. Unfortunately, Justin Bieber and Sean Kingston found that out the hard way this past weekend, as they were mobbed by fans while driving in the Miami Beach area. The 'Baby' and 'Beautiful Girls' singers were forced to call for backup -- that'd be a cop -- to help them navigate safely.

TMZ reports that The Biebs was behind the wheel of a Rolls-Royce on Ocean Drive in Miami. Kingston was riding shotgun. Sources say that the vehicle actually belongs to Kingston, but we guess that he probably has airtight and iron clad insurance if he let a 17-year-old hit the road with it! A group of fans took notice of the cruising pair, who also hit a Selena Gomez show in Florida together so The Biebs could support his gal pal, and a crowd began to gather.

Well, it's not like Justin Bieber driving a Rolls is something that won't attract attention or a throng of fans. Come on! That's a total "look at me" moment.

TMZ also reported that Bieber and Kingston, who is recovering from the jet ski accident that nearly claimed his life over the Memorial Day weekend, managed to get the attention of a plain clothes cop, who jumped to their rescue by standing guard until the crowd dispersed. They must have found something else to gawk at.

UPDATE: According to 'TODAY,' Bieber and Kingston were forced to pull over because a police officer thought Bieber was a minor and could be driving without a license. Apparently, the cop asked "What's a 12 year old driving a Rolls Royce for?" Bieber showed the officers his license and Kingston explained the car belonged to him. However, as all of this was going on, Bieber and Kingston's vehicle was surrounded by a mob of fans, causing them to require police assistance to escape the chaotic scene.

Watch the Sean Kingston 'Beautiful Girls' Video