Four people have been injured after a man allegedly attacked diners with an axe at several Chinese restaurants in Auckland, New Zealand.

Footage showed people running from one restaurant after witnesses said the man entered and started hitting people at 21:00 local time Monday (09:00 GMT.)

They told local media he was carrying a number of other weapons, including a "hammer-like thing".

A Chinese national was arrested at the scene, police said.

He has been charged with causing grievous bodily harm. He has not been named and his age has been withheld.

Police said the attack did not appear to be racially motivated and was being treated as an isolated incident.

Three people remain in hospital in stable conditions, they said.

Police rushed to the scene after receiving calls from the suburb of Albany, a popular area for dining out, with reports of attacks at the Zhangliang Malatang, Yues Dumpling Kitchen and Maya Hotpot restaurants.

A staff member at one said the incident began without warning as the man entered and suddenly "took a hammer-like thing out and attacked people sitting at a table" while a chef described the aftermath as "like a war zone".

"I saw a young person, around their 20s, with blood on their head. They stood for a moment and then collapsed to the ground," he told Radio New Zealand (RNZ).

One diner told Newshub's AM Show he saw the man take out "a massive demonstration hammer" and "swing a blow".

Another woman recounted to RNZ how the attacker hit her friend from behind with the axe.

Someone then shouted: "What are you going to do? Why are you doing it?", before the man hit her friend again, she said.

Police have not given a motive for the man's alleged attacks, but say he is expected to face further charges.

"We acknowledge how frightening this incident was for those involved, and for the wider community, and we are ensuring there is support in place for both the victims and their friends and family," police commander Inspector Stefan Saga said.