Prime Minister John Key has extended his condolences to the friends and families of the three people who died in the Hobsonville tornado.
The twister struck a one-kilometre zone in Hobsonville at 12.30pm, hitting the construction site of a new school at Hobsonville Point with deadly force.
It appears giant concrete slabs toppled onto a work truck, crushing those inside.
Seven people were injured and have been treated at North Shore hospital. Their injuries were not thought to be life-threatening.
"This must have been an extremely frightening situation for many people in the local community," Key said.
"This extreme weather event occurred in the heart of my electorate as well as Paula Bennett's electorate. I have been kept informed of the situation throughout the afternoon and am continuing to receive updates," Key said.
Labour leader David Shearer also expressed sympathy.
"Our hearts go out to the family and friends of those who were killed. It is deeply shocking to lose loved ones in such a sudden and tragic way," Shearer said.
"Our thoughts are also with those who have been injured. We wish them a speedy recovery."
Labour's Auckland MPs are already on the ground providing support and assistance to those affected" and will continue to do so in the aftermath of this terrible event," he said.
Mayor sends condolences, inspects damage
Auckland Mayor Len Brown says Aucklanders' thoughts are with
those affected by the tornado and severe rain in the Hobsonville
Brown spent the afternoon in the area with emergency services, inspecting the damage and meeting some of those affected.
"My deepest condolences and commiserations to the families of those who have died," he said in a statement.
"This is a real tragedy and my heart goes out to the community
and to the company for which the deceased were working. A number of
people are in hospital and they have my best wishes for a speedy
Up to 150 homes have suffered some kind of damage, and many of the people living in them have been relocated to Whenuapai Air Force Base.
Brown expressed his "deep appreciation" for the job being done by the Air Force and "the real pace with which they have dealt with the emergency".
"Thanks also to all the emergency services for their rapid and
hard work today, including the council's welfare staff and building
The worst of the weather now appeared to be over, but Brown appealed to people to take care driving, with flooding and debris still on roads.
"Lives have been lost, people injured and property badly damaged. Those affected and their families are in our hearts and minds."