They call the police 'feds', obviously borrowed from US TV and films, where it's been used for ages to refer to the FBI. Of course they know the metropolitan police are not the FBI, but the term seems to have been adopted and broadened to refer to police officers.
They talk of defending your 'yard', apparently a West Indian term for your home (presumably after the government yards in trenchtown, as sung about by Bob Marley, and the origin of the term 'yardie'). The BBC attributes this mix of slang to Multicultural London English, a mixture of the cultures that are either found in the city or enter consciousness through the media.
There are two terms cited that I don't know at all:
Another, widely reported in the aftermath of the chaos, urged everyone to "up and roll to Tottenham [expletive] the 5-0". There were myriad references as well to the "po po".Is 'the 5-0' a reference to Hawaii 5-0? Seems unlikely somehow, given how long ago that was on TV, but Urban Dictionary tells me this is the correct derivation.
'Po po' I'd never heard, but the BBC article says it's from The Wire. I've never seen The Wire, because I'm an idiot, and because I was busy watching Battlestar Galactica when it was on, so there's a lot of Baltimore street slang that I'm not aware of. This is my own failing, and I freely admit it. Urban dictionary just says it means police, though one entry does suggest that it means 'pissed off police officer'. I'm not sure I'm buying that, though; it smacks of folk etymology.