Uh oh! It looks like rapper Lil Wayne and Justin Bieber's manager, Scooter Braun, have beef, and things aren't looking pretty between the two men.

So what's causing the rift between Braun and Wayne?

Well, rumor has it that the debacle is over Lil' Wayne's artist and Justin Bieber's former friend, Lil Twist.

TMZ posted a video on Monday of Wayne dissing Bieber's manager. In the video, Wayne says, "I heard this b*tch*ss ni--a Scooter talkin' shit about my little brother [Lil Twist]," he continued, with one arm around Twist. "Ni--a, this my motherf*ckin' brother, anything you got to say, when you see me say it to my motherf*ckin' face."

He continues, ""And if you do happen to say it to my motherf*ckin' face, I ain't gonna make you eat them words ni--a. I'mma put them b*tches on your tombstone."

Yikes! Word to the wise: don't mess with Lil' Wayne.

For those of you confused about why Twist is in the middle of all of this, let us explain.

Billboard reports are stating that, since last year, Braun has been dissing Twist and pinning him as the reason for Justin Bieber's bad boy image in the media.

Braun has been allegedly very vocal about his belief that Twist is a negative influence on the Biebs. Braun's claims created such frenzy that Twist later moved out of Justin's home.

Naturally, Wayne was not too happy about the negative media his artist was getting and since last year things just haven't been the same between Braun and Wayne.

The reason why Wayne is bringing up "old beef" from last year still remains a mystery but perhaps Braun is back to his old ways in painting a bad portrait of the 21-year-old Texas native rapper.

Although Wayne and Twist may be against Braun, Bieber is sticking by his manager's side. Just recently, the Biebs posted a few Instagram photos of himself with Braun under the caption, "All love."

How will the battle of Wayne and Braun turn out? We'll just have to wait and see.