Home Secretary Yvette Cooper has visited Southport following a knife attack which left three children dead and nine others critically injured. Speaking at the scene, Ms Cooper said: "It's beyond every parent's worst nightmare. What should have been a children's party, having fun at the beginning of the summer holidays could then turn into something so devastating. There's deep concern about knife attacks across the country and that's why the PM has said it is a moral mission to address this." Report by Kennedyl. Like us on Facebook at http://www.facebook.com/itn and follow us on Twitter at http://twitter.com/itn