Twelve people were arrested after a 24-hour police crackdown involving more than 50 police officers.

Dubbed Operation Lucy the 24-hour operation began in Palmerston North at 7am on Thursday and involved about 50 police officers to prevent and crackdown on crime.

Inspector Brett Calkin said it began with a number of properties being searched.

Police recovered vehicles, cannabis, methamphetamine, along with several firearms in a search of two Palmerston North properties.

Acting Senior Sergeant Darren Paki said they were still investigating the legality of a number of cars found at one of the properties, as well as the cannabis and firearms charges.

Paki said 12 people were arrested for a variety of offences, including some who had warrants out for their arrest and breaches of bail.

Paki said they visited 30 families in relation to family violence and "engaged really well with them".

"It was really good for our guys to get out there in that capacity to help some of our victims and offenders."

Police also visited 20 homes where truancy was an issue.

Paki said they stopped 400 vehicles in roadside checkpoints, impounding one vehicle and issuing 80 infringement notices.

"For us that is a pretty good result, only 80 infringements issued means people are getting the message around road safety."

Police conducted 100 breath screenings but found no one exceeding the breath alcohol limit.

Paki said they conducted the stops via a mix of checkpoints and mobile patrols around the city.

Tararua police visited high schools as part of the 'Love me Not' programme to educate students about having healthy non-violent relationships.

Calkin said operations like this were carried out periodically but would increase leading up to Christmas.