A teenage girl is dead and another has been seriously injured after a quad bike accident.

Emergency services were called to the crash, which happened on a private road, at 6.44pm, in Taharoa, Kawhia.

Police said the girls had been on the quad bike at the time of the crash.

The Taupo-based Greenlea Rescue Helicopter flew to the helicopter pad based at the Taharoa iron sands mine site and retrieved the survivor on Sunday. She was flown to Waikato Hospital in a serious condition.

A helicopter spokesperson says the teenager suffered spinal and internal injuries.

'She was transported in the back of a ute, but the ambulance met them - it's pretty isolated out there and they had to get her out in a four-wheel drive."

The Serious Crash Unit are investigating the crash.

'Police offer their sympathises to the friends and family of the deceased at this tragic time,” says a statement from police.