Detective sergeant Olivia Meares said it appeared to be a violent and unprovoked attack by an unknown offender.
CCTV footage in the area indicated there were several potential witnesses who police have not yet spoken to, Meares said.
Police have previously sought information about the occupants of a white van parked in the Wesley Methodist Church carpark.
It has now been established two people got out of the van and went over to the area where the victim was stabbed before returning to their vehicle and leaving, Meares said.
Police have previously sought information about the occupants of a white van parked in the Wesley Methodist Church carpark. Photo / NZ Police
The van is white or light grey and appears similar to an older-style Mitsubishi L300 model.
Police also want to identify a man who walked past the area around the time the victim was stabbed.
He has long hair, which may be braided.
They also want to identify a man in shorts or rolled-up black pants, with a grey stripe, who was also in the area at the time.
"We believe these people may have witnessed the attack on the victim, or have information which could assist us in identifying the offender," Meares said.
"If you are able to help us identify any of these people, please get in touch with Police as soon as possible."
Police want to identify a man in shorts or rolled-up black pants, with a grey stripe, who was also in the area at the time and is a potential witness. Photo / NZ Police
Anyone with footage or information can contact police via their 105 phone service or online at https://www.police.govt.nz/use-105, using Update My Report.
People should reference Operation Wesley, file number 220729/2490 .
Information can also be provided anonymously via Crime Stoppers on 0800 555 111
