A man has been arrested after wounding four people in what appears to be a random knife attack in Auckland.

One woman was attacked at a bus stop while a couple were attacked on a beach in Murrays Bay, on Auckland’s north shore, on Thursday morning.

The violent rampage came to an end when the attacker was brought to the ground by bystanders.

Police District Commander Naila Hassan said the attack in Auckland was random and the suspect was in custody.

She said there was no indication the attack was a hate crime, as the victims were of different genders, ethnicities and ages.

“This was an extremely fast-moving incident, where our police staff responded quickly, apprehended the offender and prevented further harm to our communities,” Commander Hassan said.

She said the victims all suffered moderate injuries.

Passers-by began following and surrounding the man after he began his attack and one brought him down using a walking crutch, Commander Hassan said.

“Members of the public acted with extreme bravery,” she said.

She said the man had been carrying a large knife and suffered moderate injuries when he was apprehended. He was taken to hospital.

She said the attack lasted less than 10 minutes.

One woman, who was walking her dog along the beach when the attack happened, said a construction worker used crutches to bring down a. man.

She said she watched a man in a hoodie run down a road and begin stabbing people. He chased one teenager, who screamed.

“We thought she was being silly, she was shrieking,” the woman said.

“He stabbed two people, totally random… it all happened very quickly.”

New Zealand was the site of two violent stabbing incidents at supermarkets last year.

One was considered a terror attack while a judge found no motive could be attached to the other.

In September, a Muslim extremist inspired by the Islamic State group stabbed five people in an Auckland store before police shot and killed him.

Three of the victims were critically injured and two other people were injured in the melee, but all survived.

And in May last year, shoppers and staff at a Dunedin supermarket managed to stop a frenzied man from hurting others after he stabbed four people in a random attack, severely wounding three of them.

The Dunedin attacker, 43-year-old Luke Lambert, was convicted on four counts of attempted murder and sentenced to 13 years in prison.

-with AAP