Associate
When Lee Rigby was killed, were his killers immediately labelled as mentally ill? No. I don't then see why it would be the case here. This guy could have been radicalised by Britain First propaganda and carried out his attack knowing full well what he was doing - Anders Breivik style. Radicalisation isn't something exclusive to Muslims; it can affect any group with a grudge about government policy, perceived injustice or marginalisation.