Someone I know was seriously beaten by Police walking home from his night shift as a firefighter in the late 80s - he looked suspicious obviously because he was black. He sustained injuries which put him on light duties (ie not saving people in fires) and eventually got compensation. More recently a Sikh woman was raped and subject to horrific abuse because the attacker though she was Muslim.
I'm not in any way excusing the attack yesterday but nobody should be subject to violence or abuse because of their religion or ethnicity. Imagine being Jewish and going about your day in good old England and being killed for belonging to a faith and or ethnic group. Imagine being anybody that happened to.