Montgomery County officials launched a public-education campaign last week to combat teen drinking, focusing on efforts to persuade parents not to provide alcohol for teenage parties.

County officials estimate that about 80 percent of the alcohol consumed by underage drinkers is purchased legally by adults. Nationally, about 65 percent of alcohol drunk by minors is purchased by adults, said George Griffin, director of Montgomery's Department of Liquor Control.

Griffin said the relatively high proportion of minors who get alcohol from adults suggests that the county should target adults who knowingly buy alcohol for minors. In many cases, Griffin said, parents buy alcohol for their teenage children and friends in an effort to control and monitor the drinking, rather than letting the kids drink anywhere.

Officials from the police department and an assortment of county agencies discouraged that practice at a press conference on Shady Grove Road in Rockville.

The slogan for the two-year campaign is "Parents who host lose the most: Don't be a party to underage drinking." Fliers will be distributed through county liquor stores to anyone buying alcohol.

As part of the campaign, officials also launched a tip line for parents and teens, 301-670-SAFE, which is designed to be a sounding board for parents and a tip line for police looking to break up parties where minors are drinking.

The tip line, manned by police officers, is for parents seeking advice on planning parties with teens or on how to lay down ground rules for teens going out to parties.

Similar tip lines have been used to great success in years past, said Officer Bill Morrison, a member of the alcohol enforcement unit. The line had fallen out of use in recent years, and a recent series of fatalities among teenagers in car accidents, at least one of which involved alcohol, helped resurrect it, Morrison said.

In late September, five young people died and four were injured in Montgomery in three accidents in a single weekend. All of the crashes involved excessive speed, police said. The victims were 16 to 19 years old.

Police encouraged parents and teens to use the tip line to prevent further tragedies.

"Not only are the police the enforcers, but we're also parents," assistant chief John King said. "When we have to make that notification, to tell parents that their teenagers are no longer coming home, that is the toughest part of our job."