Emergency services were called to Hanson Grove about 9am following reports of a firearm being discharged.
A 39-year-old man was found in critical condition at the scene and was airlifted to Wellington Hospital .
Detective Inspector Haley Ryan said a dark-coloured vehicle was seen fleeing the area at speed shortly after the incident, but the vehicle has not been located.
She said police were working to establish what had happened and were urging members of the public to come forward.
"CCTV will be vital in this investigation," she said.
"We are urging anyone who has residential or commercial CCTV or dashcam footage from the Hanson Grove area or the main arterial routes of Stokes Valley to contact us."
Anyone with information is asked to contact police.
