One patient was seriously injured, one moderately and two others suffered minor injuries.
Meanwhile, two people were flown to Waikato Hospital by rescue helicopter following a serious two-car collision on State Highway 2 in Karangahake.
One of the patients was injured seriously, the other moderately in the collision which took place around 2.10pm.
Two others were injured in the crash, one moderately and another minorly who were taken by ambulance to Thames Hospital, a St John spokesperson confirmed.
Police report a fifth person was initially trapped in the collision.
The incident took place in the Karangahake Gorge and blocked a southbound lane initially, NZ Transport Agency reported.
However, the gorge has since opened fully and congestion through the area has eased.
Elsewhere, one lane of State Highway 39 near Otorohanga was temporarily closed following a serious crash between two cars, police report.
A spokeswoman said they were called to the scene of the crash along with St John on Kawhai Rd around 2.45pm.
Four people were injured, two seriously, one moderately and the other minorly. All were being transported to hospital, the spokeswoman said.
She said two tow trucks were called to remove the vehicles from the scene of the crash.
NZTA reports the northbound lane had been blocked between Honikiwi Rd and Waitomo Valley Rd.
However, SH39 is now open and congestion is clear.
