Members of a Northland church are "deeply saddened" and in mourning after the deaths of three of its members in a devastating crash near Dargaville on Monday.

Susie Stewart, 48, her daughter Sadie, 16 and family friend Jamie Wearmouth, 18, died when their 4WD ute hit a tree on Baylys Coast Rd, near Dargaville in Northland, about 6.45pm. Three others were seriously injured in the crash.

Mrs Stewart and the two teenagers were members of the Plymouth Brethren church, previously known as the Exclusive Brethren.

Church spokesman Doug Watt said the trio's passing would be keenly felt at the church's Westmount School Kaipara Campus, where Sadie and Jamie were students.


"Susie was a much-loved volunteer helper at the campus over many years. Sadie was in Year 12 at Kaipara; Jamie was in Year 13."

Mr Watt said three other young people from the Kaipara campus were injured in the accident.

The three fatalities were all from Northland, he said.

"The loss is a tragedy for the family and the wider community and will impact the school in the days ahead. Staff and students at Kaipara are being provided counselling during this very difficult time. Our thoughts and prayers are with the families involved."

The families had requested privacy.

Mrs Stewart was the front-seat passenger of the vehicle, Sadie was the rear left-seat passenger and Jamie was in the middle rear seat.

Northland road policing manager Wayne Ewers said the vehicle, which the three were travelling in, left the road on a right-hand bend before it hit a large tree.

The ute was carrying seven people. Its driver and rear seat right-side female passenger received minor injuries, while the two males on the tray were thrown from the vehicle at point of impact with the tree, landing a short distance away.

Both males were taken to Whangarei Hospital with non-life threatening injuries.

The Serious Crash Unit is investigating the crash and will look into what charges, if any, may be laid against the driver.

Deputy chief fire officer Michael Ross, of Dargaville, said as firefighters worked under lights to free those trapped, a cross nailed to the tree above the damaged vehicle brought the situation home.

"It was pretty eerie," Mr Ross said.

Police confirmed the cross marked the death of a 39-year-old Dargaville man, who died in December 1997 following a crash in the same area.

The three deaths bring Northland's provisional road toll for 2016 to 18, compared with 22 for the whole of 2015.