Police in Dover are warning pubs and clubs to make sure their bar staff ask customers for identity.
It follows a number of recent complaints of underage drinking and a recent assault where the victim was just 16 years old.
The assault occurred in the Party Bar in Church Street, Dover, late on Friday 1 February. The victim was in the bar with her friend, another underage girl, when she was assaulted by an older girl.
She suffered a number of minor injuries including swelling around her eye and a swollen jaw.
Anyone who witnessed the assault is asked to contact Kent Police on 101 quoting crime reference ZY/3301/13.
PC Chris Stephens, Licensing enforcement officer, said: "Licensees have a legal responsibility to ensure no one underage is served alcohol on their premises.
"In a well-managed pub or club I would expect all bar staff to ask anyone who looks underage for their identity and to make sure the ID presented is genuine and valid. It is an offence to serve underage people alcohol and bar staff can be held liable and could be fined.
"In addition to this the premises could be subject to a Review which could result in the licence being suspended or revoked.
"I would also urge parents to ensure they know where their children are and that they are not drinking alcohol in public and certainly not visiting pubs and clubs."