Conditions at the time of the crash were reasonably dark, he said.
The road is part of the "Million Dollar Highway" and Crowe said drivers certainly had to know what they were doing to drive parts of it.
The road is tar-sealed.
A karakia had been performed at the crash scene, with police and logging truck drivers "who were close at the time" present.
Grim scene as hearses arrive
By 11.30am the hearses had arrived and were let through by police manning a cordon on the road leading to the crash scene.
People who were visibly distraught had also arrived at the cordon.
Police at the cordon surrounding a crash scene in Kaingaroa Forest where four people were killed. Photo / Stephen Parker
One person sitting in the passenger seat of a ute was visibly distraught, holding their head in their hands as the ute was also let through to the crash scene.
The area is remote and isolated but security staff were earlier stopping access to the forestry roads. The reporter at the scene said this was the only human interaction she had seen. Security staff have now been replaced by police.
Timberlands chief executive Robert Green said his company was co-operating with police.
"We can confirm that the people involved work for a contractor to Timberlands as valued members of our wider forestry team.
"Like everyone else in the area, we are shocked and saddened by what has happened. We pass on our condolences to the families, whānau and everyone affected by this.
"We are ready to provide assistance to whānau and families, but the police have asked that we not approach anyone until they have completed their own process for notifying next of kin."
A St John communications spokeswoman confirmed one person has been flown to Waikato Hospital in a critical condition.
Police at the cordon surrounding a crash scene in Kaingaroa Forest where four people were killed. Photo / Stephen Parker
The crash happened at the intersection of Bonisch Rd and Parapara Rd in the Kaingaroa Forest. Image / Google Maps
Police were called at around 6.40am to the crash between a car and a truck.
UPDATE 29/07/19 06:39: Traffic incident in Kaingaroa Forest . 5 patients treated, 1 patient transported to Waikato Hospital. Helicopter dispatched. For more details refer to Police. https://t.co/rbhYAZNyrS
A St John alert says they had five patients at the scene.
As of yesterday, the road toll to date stood at 210 deaths on the roads this year.
A Ministry of Transport spokesman said they were in the process of adjusting those figures as a result of today's horrific crash.
The number of deaths on New Zealand roads the same time last year was slightly higher, with 219 road deaths confirmed between January 1 to July 28, 2018.
Last year's total road toll was the highest since 2009, with a total of 381 people killed on our roads. In 2009, the annual road toll recorded was 384.
