Two men are dead and two more are fighting for their lives after incidents early on New Year's Day.
Auckland police are looking for a weapon used in an assault on a 27-year-old man who was found dead in the Auckland suburb of Panmure around 4.20am.
About two hours earlier, a 29-year-old man was hit and killed by a taxi while walking on a Hokio Beach Road near Levin.
His death brings the holiday road toll to five.
A 64-year-old man, who was stabbed in the head and neck after confronting a man lurking outside the caravan he was staying in at Waihi Beach, is in Waikato Hospital and fighting for his life.
In Hawke's Bay, a 25-year-old man who was pulled unconscious from the surf at Waimarama Beach about 1.30am was in a critical condition in hospital.
At traditional hotspots in the Bay of Plenty, police made 91 arrests with drunk teenagers causing the biggest headache.
In one incident before midnight at Mount Maunganui revellers saw a man stomping on the head of another man several times.
The offender was arrested, but late in the day police were still looking for the victim who had been seen bleeding heavily as he staggered through the crowd.
Police Deputy Commissioner Mike Bush, who was on the beat in Wellington on New Year's Eve, said there were no major incidents around the country.
"As usual, alcohol was at the root of most disorder but changes in the police approach seem to be having a positive effect," he said.
"Police officers are now working with licensees throughout the year to agree how bars should be run and how to keep people safe.
"It's a joint approach that's been very successful. We hardly need to go into pubs now - the bar staff should take care of that while we take care of what happens on the streets."
On the final day of the three-day Rhythm and Vines music festival in Gisborne a crowd of 30,000 saw in the New Year with music and fireworks.
Organisers say around 3000 were still awake to see the sun rise and police area commander Inspector Sam Aberahama says there were only 15 arrests.
While the fireworks lit up the Waiohika Estate, strong winds forced the cancellation of the display in Wellington over safety fears.
In Auckland the pyrotechnics from the top of the Sky Tower failed to impress internet piracy accused Kim Dotcom who vowed to improve things.
"Auckland deserves bigger fireworks. Let me look into that for next year," he tweeted.
Nelson Bays enjoyed a violence-free start to 2013 with police reporting no assaults and their 28 arrests were for liquor ban breaches, disorder and drunkenness.
In Christchurch police made three arrests at a concert in Hagley Park and a handful of other arrests in the city.
A 22-year-old Christchurch man was being treated in Wairau Hospital after falling from a balcony at a house in Tory Channel in the Marlborough Sounds while an elderly Whangamata woman was woken after a bolt was fired through a glass door at her home.