West Midlands Police has launched a new code-cracking initiative to help tackle under-age drinking.

Under the scheme, which forms part of the anti-crime Operation Strikeout programme, officers will be able to trace outlets selling alcohol to minors even in the absence of till receipts.

The clampdown came as supermarkets nationwide were warned they had four weeks to "get their their houses in order" and stop selling alcohol to under-age drinkers.

Police can now check the lot codes from bottles and cans of alcohol that reveal the time and date of manufacture. From there, it is a relatively simple task to trace the supplier of the alcohol.

Superintendent Andy Bebbington, the co-ordinator of Operation Strikeout, said: "The lot codes, which are stamped on bottles and cans by the manufacturers, are specific to a limited number of stores within any given area.

"By finding out where young people are from, you can trace the bottles back to the premises where the alcohol was sold.

"There is an established link between alcohol and violent crime. To be able to pinpoint those retailers who sell to under-age drinkers is another tactic we can use in combating the problem."

Meanwhile, Ken Jones, who is to leave his post as Chief Constable of Sussex to become president of the Association of Chief Police Officers (ACPO) warned he would revoke the right of offending stores to sell liquor.

"My message is to the trade please help us be getting your houses in order.

"This new legislation gives us more powers in November - we will be using them," he said.