Police believe a rental car was on the wrong side of the road when it collided with another car, killing an American woman.
The rental car passenger died in the head-on collision in rural Waikato that left her husband in a critical condition.
Police say the pair, believed to be US tourists, were hurt when their rental car collided with an oncoming vehicle near Putaruru at 6pm yesterday.
The woman died at the scene and her husband, who was driving, was flown to Waikato Hospital after being cut out of the car, a police spokesman said.
A hospital spokeswoman today said he was in a serious but stable condition.
Two people in the other car were not injured.
Police are still investigating the crash.