Dunedin police last month revealed a group of teenage girls were found heavily intoxicated in central Dunedin earlier this year.
The mother of one of those girls said yesterday the problem was out of control.
''All the young ones from Dunedin are getting the alcohol from these sober drivers,'' the woman, who did not wish to be identified, said.
''It's a known thing, but we can't do anything about it - we can't stop it.''
Parents needed to be wary about what their children were involved in, she said.
''They are 14-year-old girls getting in the car with strangers - the danger is there. You don't know whether that's safe; it could be anybody picking them up.
''You don't want to believe it is happening, but it is and it's getting particularly bad in Dunedin.''
She feared young girls could be taken advantage of financially and sexually.
''It didn't happen on this occasion, but do I think it's happening? Yes,'' she said.
Police were told because of a lack of evidence, the matter was unresolved.
This week's arrest pf a 21-year-old marked a breakthrough in the police's pursuit of the issue, Paulin said.
''This is the first time all these ducks have been lined up. Hopefully, this may raise concerns and more people will come forward.''
Police said the two girls sneaked out of home and went to a party after consuming the alcohol.
''[The 21-year-old] picked up a 13-year-old and a 14-year-old, took them to a nearby bottle store and purchased a pack of RTDs for them,'' he said.
It was the first time the teens had sourced alcohol this way but ''it is happening regularly'', Paulin said.
''Apparently, it was very common knowledge among their peers, so they thought they would give it a go. They consumed the alcohol and got into some strife later on.''
The teens were taking a big risk by getting into cars with strangers.
''The big concern is you get these 13- and 14-year-olds getting in these boy-racer cars and you don't know what they are going to drive like,'' he said.
''They are placing themselves in a really vulnerable situation.''
It was a wake-up call for the girls' families and Paulin had spoken to both teenagers.
He warned other parents to be vigilant about their children's social media use and drinking behaviour.
''Be wary of what kids are doing on Facebook and have a wee look at who they are having interactions with, and be aware they will probably have two sets of Facebook [accounts],'' he said.
