One of the eight victims of a horrific head-on collision near Taupo was a long serving member of Scouts NZ.

The woman, who has not been officially named by police, died at the scene of the crash, along with the driver of a van and six passengers.

The sole survivor, a 9-year-old boy who was in the van, was taken to Waikato Hospital in a critical condition but was stable last night.

Police say it is too early to know what caused the crash but it appeared one vehicle crossed the centreline.

The Herald understands some of the victims were children and a booster seat could be seen on the road near one of the mangled cars.

Scouts NZ was last night supporting the family of the SUV driver, who had been with the organisation for many years.

Chief executive Joshua Tabor said the woman was travelling from Hamilton to Taupō after attending the closing dinner at the National Caving School in Waitomo on Saturday night.

She was due to meet a senior volunteer before continuing to a work meeting in Palmerston North.

"We are committed to supporting her family as best we can given the sudden and tragic circumstances.

"We also extend our support and have offered counselling to our staff and volunteer community, many of whom worked closely with her during her long tenure with Scouts."

Taupō mayor David Trewavas told the Herald the wider community was reeling after the mass-fatality crash.

It followed another fatal crash near Taupō at the beginning of this month in which five people lost their lives, all of them members of the same family.

"[It's] just unbelievable, really, that this could happen so close to the previous incident and with more fatalities, the district is in absolute shock," Trewavas said.

Bay of Plenty Road policing officer Inspector Brent Crowe said yesterday's accident was on State Highway 1 near Atiamuri at 10.30am in wet conditions.

"It appears for whatever reason one of the vehicles has crossed to the incorrect side of the road on a moderate left-hand bend."

Police say they had to call in the Disaster Victim Identification team to help confirm how many died due to the "catastrophic nature of the crash".

Crowe said it could be days before more information could be released about the victims "because of the type of crash it was and the injuries sustained".

He said to describe the scene as a complete tragedy would be an understatement and the main priority for police was to look after those who had died, for the sake of the families of those involved.

"There will be also, obviously, a thorough investigation into why the crash has happened and that could take a considerable period of time."

He said support was available for staff.

"The team is passionate about road safety and we have a trauma policy in police which is activated for major incidents like this."

Local residents have expressed concern about the area, describing the scene of the crash as a "bad stretch of road".

Some say they avoid using the highway because of all of the accidents in the area.

As of April 25, the Ministry of Transport was reporting 125 people had died on New Zealand's roads since the start of the year, two less than at the same time in 2018.

Yesterday's accident is one of the deadliest in terms of the number of people killed in a single car, van or SUV.