Two people remain in a serious condition after being airlifted to Royal Darwin Hospital after being airlifted from the scene of an accident on the Stuart Highway.

A woman was flown to RDH by Careflight helicopter yesterday morning after the crash involving a campervan and a tow truck near Emerald Springs roadhouse, about 130 kilometres north of Katherine.

The two people are believed to be aged in their 60s.

A Careflight doctor and nurse from Darwin joined a medical team from the Pine Creek Health Clinic to stabilise the woman, who had suffered multiple injuries.

She was flown under intensive care to RDH.

Northern Territory Police had blocked all traffic on the Stuart Highway near the crash scene to allow the helicopter to land.

Careflight director Ian Badham said the injured man was taken by ambulance to Katherine.

“Only one critically injured patient under full intensive care monitoring can be taken in the helicopter,” he said.

“We can take two lesser injured patients but [with seriously injured people] it is best for only one to go in the helicopter.”

Mr Badham said a Careflight King Air plane flew to Katherine with a second medical team aboard to move the injured man to Darwin.

The man and woman remained in intensive care last night.