I don't know much about UK Politics, but I have seen a noticeable trend in the US that when an immigrant commits a crime, anti-immigration factions immediately use it as a call to arms. "An immigrant committed a crime so we must deport all immigrants due to their intrinsic danger" type stuff. Yet, 100s of white Americans can commit crimes, even specifically political terrorist attacks, and no one in those factions will bat an eye or call out white Americans for their intrinsic danger.
I see no value in this type of rhetoric. It is searching for an incident to justify an often racist or xenophobic cause.