His name has since been suppressed pending his next appearance in court.
The victim's family was "understandably devastated", Barry said.
"We believe the victim was walking along the pathway and was on his way home."
The man's body was located up the pathway, very close to the boardwalk.
Police don't believe the victim was known to the offender, nor do they believe robbery was a motive. Police are not in a position to release the victim's details.
Albert-Eden local board chairwoman Margi Watson said the community was reeling after the incident.
"It's a significant and sad event for the wider Mt Albert, Sandringham, St Lukes community ... It should never have happened and that's what's incredibly sad, someone's lost their life."
She said the police's announcement on a person of interest was a big step.
"I would hope that our community take notice of what the police have said about not approaching, but if they have information, they share it."
There have been several gang-related shooting incidents in Auckland this week, but Barry said there was "absolutely no indication" the man's death was gang-related.
The victim's body was found by adult passersby. Police were notified about 6.55pm and believe the crime was committed shortly before, Barry said.
"There would have been other people around ... our message to them is please contact us if you were in the area because you may hold that vital piece of evidence that will assist the investigation."
They are also seeking CCTV and dashcam footage which may be of interest.
• Police say any information that may assist with the investigation can be reported by calling 105 and quoting file number 220524/8192, or Operation Volans. Information can also be provided anonymously via Crime Stoppers on 0800 555 111.