Whilst my thoughts are with those stabbed and their families, I'm sure Reform will already be shouting about immigrants, even though the police have already said they believe it is "an isolated, mental-health related incident".
Woman arrested after four men stabbed in London's Covent Garden - follow live
Two of the four men have been released from hospital, with police saying they believe this is "an isolated, mental-health related incident".
bbc.co.uk