A high-pitched whine that only under-25s can hear is being used to drive off troublesome teenagers from a parade of shops.

Customers are flocking back to stores in Hunwicke Road, Greenstead, Colchester, as gangs of youths are sent packing by the noise of the hi-tech Mosquito system.

The scheme is yet to win official backing from Essex Police, as there are fears that subjecting youngsters to the noise could breach their human rights.

but residents and traders alike have hailed it as the answer to their prayers.