Apparently this was a triad gang killing, and it was bloody and nasty. Also see the BBC piece.
In over-globalized London, misery from all over the planet arrives and feeds on the profits of drug-dealing, money-laundering, extortion, you-name-it.
And they exist because above them are ever larger layers of over-specialized economic citizens who are so removed from Nature, the Planet, and Love, that they in one way or another are decadent, selfish, greedy, paranoid etcetera.
Institutions deal with it speedily, and the rest of the world goes on its merry way, living in its Matrix of Illusions and Delusions. Which reminds me of a superb Italian economist who had her book reviewed on the BBC World Service last night, see next post about Rogue Economics.