To ask the Secretary of State for the Home Department what proportion of Class A drugs supplied to the UK market he estimates were intercepted in each six month period since January 2000. 
I have been asked to reply.Work is under way to improve estimates of the total supply of Class A drugs to the UK but law enforcement agencies are currently working on the basis that in 2001–02, they took out an estimated 10 per cent. of heroin and 21 per cent. of cocaine supply to the UK. Information for other periods and other Class A drugs is not available.