The second victim was taken to hospital with moderate injuries.
The alleged offender was arrested at the scene.
“A scene examination is now under way and the road is expected to remain closed for some time,” police said.
“Diversions are in place, and motorists are asked to avoid the area.”
Hato Hone St John said they were notified about the incident and treated one patient who was transported to Whakatāne Hospital in a moderate condition.
A St John spokesperson referred further inquiries to police.
More to come.