Fabolous and Ray J were among the tens of thousands of people that were in Vegas for the Mayweather and Ortiz fight.

What most of those people didn't know is that there would be another great fight in the lobby of the Palms hotel.

The beef between Fabolous and Ray J started after Fab commented about Ray J's cameo on '24/7'.

After watching the documentary about the days leading up to the Mayweather fight Fab hit Twitter to dog Ray J.

The two ran into each other on Sunday after the fight and according to Ray J, it was on.

"When I seen him  I was with Floyd and 50 and he (Fabolous) tried to say, 'Don't touch me', and I touched (punched) that n**ger... I got detained... I got kicked out of the motherf**king Palms hotel! Police arrested me, handcuffs..."

After Fab heard about Ray J describing the incident on the radio, he decided to hit Twitter once again.

Fabolous never calls Ray J out by name, but it's obvious who he is talking about.  Will this turn into a full blown beef?  It does not seem like it would be in Ray J's best interests if it does.  Check out the video from TMZ of him being hauled out of the Palms.