Two Northland liquor stores have been caught selling alcohol to minors in the latest sting carried out by police and public health officers.
The operation involved 17-year-olds trying to buy alcohol from 28 licensed premises in the Hokianga and Kaipara areas.
One outlet in each area sold alcohol to the underage volunteers.
Sergeant Michelle Row, alcohol harm prevention officer for Kerikeri Police, said the result was disappointing - although the one out of 10 Hokianga outlets that broke the law was an improvement on last time.
"One sale is one too many. As a community, we need to have confidence that license holders will not sell alcohol to our youth," she said.
All outlets were expected to have robust systems for checking customers were not underage, especially in Northland's more vulnerable communities.
Meanwhile, sergeant Tai Patrick was also let down by the result in Kaipara, where one out of 18 premises sold alcohol to the 17-year-old.
Staff should ask for identification from any customer who looked under 25, he said.
"No identification, no sale. It's that simple."
Selling alcohol to underage customers can have costly consequences, including the temporary loss of the outlet's liquor license.
It is not known what the penalties were for the latest outlets caught breaching the Sale and Supply of Alcohol Act 2012.
Selling alcohol to underage customers could have costly consequences, Patrick said.
Police were currently seeking temporary suspension of the outlets' store and manager licences, in accordance with provisions of the Sale and Supply of Alcohol Act 2012.