Brandon Moase said he and his friend were ordered to their knees in a street in west Auckland, handcuffed with guns pointed at them, before being released 15 minutes later after police admitted they'd got the wrong people.
Moase, 29, said he was traumatised and had not been offered any official apology or help.
"From what I remember, about four or five police with guns pointing at me and my friend. It was pretty scary, and [I was] also confused - I didn't know what the hell was going on," Moase said.
His one-year-old son was in the car surrounded by armed police.
"They had us in handcuffs, searched my car for five or 10 minutes, then pretty much told us we were free to go because they had the wrong people," he said. "They didn't read us any rights or anything, didn't apologise."
Police said they had been responding to a call regarding an aggravated robbery involving a firearm shortly before midday on Saturday in west Auckland, and were looking for two people who had fled the scene on foot.
"While police were in the area looking for this pair, two men were detained in Glenmall Place in Glen Eden, because at the time it was believed they were connected to that incident, based on the information that was provided to us," Acting Area Commander for Waitematā West Inspector John Thornley told Morning Report.
"Further inquiries determined they weren't involved. They were then released.
"Once it was clear the men were not involved in the earlier incident I'm advised that our officer apologised and my understanding is the men accepted that apology. The follow-up since is referrals to our partners in Victim Support for those involved and there'll be a further follow-up with the men as well from police."
Thornley said officers are allowed to be armed in a situation where they believe involved a weapon.
"I certainly accept this was an upsetting situation for them. In something like this it's our priority to ensure the community is kept safe and that people of interest to us who may be armed are brought into custody without further incident.
"[Our staff] are put into situations like this all the time and have to make split-second decisions with incomplete information. They do so with the right intent and that's what's happened here. That's not to take away from how upsetting it would have been for the people involved and for that we apologise."
Thornley said police haven't found the two people they were looking for and are making further enquiries.