FIVE out of 10 off-licences targeted in a sting operation in Accrington were caught selling alcohol to an under-age boy.
Accrington Police, in partnership with Lancashire Trading Standards, visited the shops on the Saturday before Christmas.
A 15-year-old boy was briefed to enter the premises and try to buy alcohol.
At five of the off-licences he was sold the booze unchallenged.
Police have issued each of the traders who sold the drink with an £80 fixed penalty notice.
A record of the operation has also been logged with the licensing department at Accrington Police Station and if the guilty shops fail any future test purchases, their personal and premises' licences will be in jeopardy.
Both police and Trading Standards say they are extremely disappointed that so many of the premises they visited had made sales.
PC Les Sholicar, licensing officer, said: "If this trend continues then we will have no alternative but to take positive action and this may result in offenders losing their licences."
Town centre policing team sergeant Ian Corbett added: "We have worked closely with trading standards officers to try and reduce incidents of young persons purchasing alcohol from these premises.
"My plea to all off-licences in Accrington is to challenge any young person. Simply ask for identification and if in doubt do not sell."
All off-licences in Hyndburn have been given literature and posters promoting the Challenge 21 campaign that suggests staff challenge any person attempting to buy alcohol who does not appear to be 21 years old.
If they can produce proof they are over 18 then the sale may take place.
If not, they should be refused and asked to return with proof of age.
Acceptable documents are a photo driving licence, a passport or an accredited proof-of-age card.
Details of where to obtain proof-of-age cards are available from most licensed premises, the licensing department at Accrington Police Station or a trading standards office.