Knife crime operation draws blank / BBC, 5 August 2008
http://news.bbc.co.uk/1/hi/england/beds/bucks/herts/7542618.stm

"More than 400 young people were searched in an operation to tackle knife crime - but not one of them was carrying a weapon. The crackdown in Waltham Cross, Herts, on 25 and 26 July and 1 and 2 August was in response to recent stabbings."