Syringes and white powder were scattered at the scene where a man fell out of a moving car in Porirua yesterday, a nearby resident says.
The man is in a critical condition in hospital after he was found badly injured on Warspite Ave about 4pm on Sunday.
A man who lives nearby did not witness the incident, but said he did spot small plastic bags of white powder strewn across the road afterwards, as well as syringes.
He said another resident was on the scene at the time, and told him others had called for a defibrillator.
He believed the incident was "definitely drug related".
One person has been arrested in relation to the incident and charged with driving while disqualified and with supply of methamphetamine. The person will appear in the Wellington District Court.
Police said the matter was still under investigation.
Detective Senior Sergeant Christiaan Barnard said he had not seen any of the ambulance documentation for the victim but confirmed police recovered a small quantity of drugs at the scene.
People who found the injured man initially thought he was the victim of a hit-and-run, but other witnesses then came forward to say they had seen him fall from the vehicle.
"But we haven't established whether he's jumped from the vehicle or whether he's been pushed from the vehicle," Barnard said.
Police had now identified the man and were contacting his next of kin.
They had appealed for sightings of a black Mercedes, registration GPW495, that may have been seen driving erratically near Waitangirua Mall.
The man who saw the drug paraphernalia on the street said there was a police evidence vehicle with about half a dozen bags of evidence being loaded into it parked near the scene.
"That was a lot of evidence that they were putting away."
The victim remained in a critical condition in hospital.
Members of the public with information on the incident have been urged to call the Wellington Police Crime Squad on (04) 381 2000, or Crimestoppers anonymously on 0800 555 111.