Staff at three village pubs in County Durham have been issued with £80 fines after selling alcohol to teenagers.
An undercover test purchase operation using two 16-year-old girls was carried out by police on Saturday.
The girls were served alcohol at The Ram's Head in Langley Park, The King's Head in Lanchester and the Jolly Drovers in Leadgate, near Stanley.
Insp Andy McConnell said more operations to crackdown on underage drinking would take place.
He said: "We hope the issuing of these first fixed penalty tickets will serve as a warning to other licensees that their premises could be next."