A teenage girl is in custody after driving into a man, crushing him against another vehicle and leaving him with "horrific" head injuries, when he tried to stop her stealing a neighbour's car, police say.
The quick actions of an off-duty nurse meant the man was "lucky to be alive".
The 65-year-old man was among neighbours who tried to prevent the girl, 15, from stealing a Subaru Outback from a home on Casuarina Dr, Rapid Creek, on Monday night, police said.
"Unfortunately, she reversed the vehicle and collided with one of the neighbours causing some crush injuries to his body," said Detective Acting Senior Sergeant Jakson Evans.
"All reports are that it was quite horrific when (responders) first attended.
"We've a good Samaritan who has attempted to do the right thing and he's come away with some very serious injuries.
"I would say, without the early intervention that came from the off-duty nurse and others in the area that he is lucky to be alive.
"I would certainly ask that everyone calls the police in the first instance before trying to intervene."
Off-duty nurse did 'terrific job'
The man was left with serious lacerations to his head and a fractured arm. He was taken to Royal Darwin Hospital where he was in a stable condition.
St John Ambulance regional manager Andrew Everingham said the victim needed significant treatment.
"When crews arrived the patient was in the care of an off-duty nurse who has done a terrific job applying first aid to that patient," he said.
"Luckily in the Territory we have an amazing community and people want to get out there and help.
"I'd encourage everyone out there to do a first aid course."
Girl's '90-minute' joyride
Police believe the car was then in another crash in the same suburb.
The late-model station wagon was seen driving erratically five kilometres away in suburban Malak then travelled another 21 kilometres to rural Coolalinga where Palmerston police arrested the girl about 90 minutes after the car was allegedly stolen.
She remains in custody.
Detective Acting Senior Sergeant Evans said the girl was known to police and investigators would allege the car keys were stolen from the locked house.
