A store in Chesterfield has had its alcohol licence suspended following a council surveillance operation prompted by complaints from the public.

Derbyshire County Council has imposed a one-month licence suspension and four new conditions on Walton Stores. The action followed a joint investigation between trading standards officers and Derbyshire Police. Concerns were raised by five members of the public and the Chesterfield Violence, Alcohol and Licensing Group.

The licence review hearing revealed that council officers watching the off licence in St Augustine's Road in July 2010 saw alcohol being sold to a person whom they knew was under 18.

A spokesman for Walton Stores said they were caught out by fake ID, which is a problem in the summer "when a large number of kids from the estates hang out". He added: "All we can do is keep asking for ID."

Under the new conditions, the shop must improve CCTV, provide extra staff training, adopt a proof-of-age scheme and tighten up the system for recording refused sales of alcohol. The county council enforced the action under the Licensing Act 2003.