Police have given more detail about a crash that killed four people at Muriwai Beach tonight.
Inspector Mark Fergus said police were alerted to the crash by passers by and arrived to find four men dead at the scene.
Earlier reports of a 12-year-old boy being among the victims were incorrect, he said.
But he could not say how old the victims were.
He said police were still working to identify the victims and notify their families.
Police had recovered all four bodies.
"At this time we have recovered all the deceased, the vehicle is being removed from the beach and now we're commencing our enquiry into what took place," he said.
Mr Fergus said it was too soon to say whether speed or alcohol were factors in the crash, or if the occupants of the 4WD had been wearing seatbelts.
He said it was unclear why the crash happened. Reports of the truck hitting a log had not been confirmed and police found no log at the scene.
An Auckland Westpac Rescue Helicopter spokesman said the crew was tasked to an area of Muriwai, about 20km up the beach.
It appeared a vehicle had been travelling at high speed along the sand, close to the water's edge, where it has hit something - possibly hard sand - and rolled multiple times.
"On arrival, the vehicle was in the surf and three patients were deceased, having been ejected from the vehicle. A fourth person, trapped in the vehicle, was found alive."
Intensive care flight paramedic Russell Clarke said: "Our crew worked extremely hard to save him, but unfortunately our attempts were unsuccessful due to the extent of his injuries."
The crew transported the deceased male patients back to the Surf Lifesaving Club and left the scene just after 6pm.
Police initially said three people had died and a 12-year-old boy was critically injured. However, they later said all four occupants had died.
"Police and other emergency services are racing against the tide and fading light to recover bodies and evidence," a police statement said.
The police serious crash unit was investigating.
Footage on One News shows the 4WD badly damaged, standing in the surf, the tide swirling around and rising.
A police officer is seen alongside a digger and rope as the recovery effort began.
TV3 footage shows emergency services vechiles on the beach and what appears to be a body covered by white sheet.
Gloved police and firefighters walk along the tide line retrieving pieces of wreckage from the sand.
Other firefighters are seen dragging a tarp up the beach with a heavy object on it, possibly another body.
The crash happened about 3.45pm some 1-2km north of the southern end of the beach.
Muriwai Surf Club callout squad coordinator Mark Goodhew said he had taken the police to the scene of the accident, but was unable to elaborate further.
Conditions for driving on the beach would have probably been idyllic, Muriwai Motorcamp camp manager Steve Shearing said.
He said it had been a mostly pleasant day in Muriwai and low tide was about 3.30pm.
"If the weather's fine, it gets busy. People can't wait to get out."
Four-wheel-drive and equestrian activities were popular in the area.
"I went down about 3 o'clock just for a look and the car park's pretty full."
He said minor crashes were not unheard of but the vast majority of people who drove on the beach did so responsibly.
"There's a large amount of people doing it, small amount of trouble."
Mr Shearing said rangers usually managed the beach well and made sure drivers didn't get into trouble.
Muriwai resident Richard Pamatatau said he could see flashing lights north of the main settlement, but was unsure of their exact location.
He said most four wheel driving was done at the unpatrolled part of the beach, north of the riding centre and creek - the direction in which he could see the lights.
"These people driving on the beach are often travelling at great speeds so while an accident like this is tragic, it's not surprising."
Staff at Muriwai Top Shop heard multiple sirens as police and emergency services rushed to the beach.
Shop staff said it had been a busy weekend in Muriwai.
New Zealand Four Wheel Drive Association president Tony Burgess said there were a lot of people driving on Muriwai beach - including parents with kids - with little experience, and speed was possibly a factor in today's accident.
"The normal road rules apply when you're driving on the beach, and it's not as easy as it looks.
"You shouldn't twist and turn or break hard and you shouldn't go into the water," he said.
Mr Burgess said the organisation wanted people to be aware that there was a bit to learn before driving on the beach - and there were hazards, like logs, buried cars, and other beach users - to think about.
"We just want people to stick to the road rules really. And keep their seat belts on."
A permit is needed to drive on Muriwai Beach and can be obtained through the Auckland Council website.
Vehicles on the beach must have safety equipment, stay off the dunes and slow down around people or animals.
The speed limit around the Coast Rd entrance is 30km/h, increasing to 60km/h north of Okiritoto Stream.
All the sand dunes, the Defence Force bombing range and the Department of Conservation-managed Papakanui Spit are strictly out of bounds.
In July 2004, three people died after a four-wheel-drive rolled on the beach.
North Shore residents Soon Sung Yim and his wife Myeoung Heui Kim were killed, as was Insoon Son, a visitor from Korea.
Two other people were injured in that crash.
The newly upgraded Waitaha Reserve has been officially opened in Welcome Bay, Tauranga.