To be 'brakked up' is the UK street slang term for being beaten up. Not so frequently used since 2010, telling someone "you are going to be brakked up" was most prevalent within the black gangsta community, but also common with some chavs. It is commonly recognised as a colloquial modification of the term to 'break up.'
Bert: Eh lad, you gots me wacky backy?
Jemal: Yeh, bruv.
Bert: Sound. Ayy, m8! I forgot meh moneh.
Jemal: Fam, I swear down, you's gon' get brakked up 2nite.