As you want to know so badly, one of them hasn't got a passport. But the judge did not reccomend he be deported at the end of his sentence. Four of the six were let out of a previous prison sentence early under the early release scheme, which is supposed to monitor them closely until they no longer pose a risk.
So, abject failure all round. This isn't simply about race, much as you wish to place me in the nazi box. It is about law and order, the breakdown of communities and culture, public services and health.