"Upon arrival the brigade found two people trapped in a vehicle," Mr Radden said.
The car in which two people were trapped was in a ditch on the side of the road. The other two cars were approximately 20m further down the road.
Mr Radden said they used rescue equipment to extricate the first person. The second person was freed by 4.50pm.
Sergeant Trinity Milham said the driver had spent an hour trapped in her car, suffering from serious multiple leg injuries.
Tauranga ambulance shift manager Shand Park said there were eight patients in total.
Tauranga Hospital communications manager Diana Marriott said all four who were hospitalised were from Auckland.
One was a 60-year-old female who was in a serious condition and had been admitted to the intensive care unit.
Two other females, aged 29 and 66, and a male aged 64, were in a moderate condition and were still being assessed.
A female occupant of one of the northbound cars, who was not hospitalised, was left visibly shaken.
"I'm grateful to all the people and to God, who allowed me to live another day," she said.
She and the male occupant of the car had blankets wrapped around their shoulders and were sitting at a picnic table near where the accident happened.
The woman said two cars had been travelling northbound and the third was travelling southbound.
This weekend was a horror one on the region's roads with three people killed in one crash in Atiamuri, and another person dead in Mangakino.
