Police in Waikato say a crash on State Highway One, at Horotiu, which left two people in a critical condition could easily have been much worse.
The collision between a car and a van, which happened about 8.30am on Saturday, closed the road.
Police say it appears the driver lost control on a corner and the car slid into oncoming traffic, critically injuring the driver and front seat passenger.
Both men, who are in their twenties, are in Waikato Hospital's intensive care department.
The driver of the van suffered minor injuries, but at the time was carrying five disabled children who were shaken up by the ordeal.
Senior Sergeant Jeff Panno says it was a very close call and there could easily have been more injuries.
He says initial indications are that speed, alcohol and fatigue were contributing factors to the crash.