One seriously injured after reported assault in Bayfair Shopping ...

Armed police attended the mall where a young woman was reportedly injured. Photo: RNZ / Angus Dreaver

Police say they are investigating reports of an assault at the Bayfair Shopping Centre in Mt Maunganui.

A witness told RNZ that she saw a young woman taken away on a stretcher and she heard that she had been stabbed.

Police said one person was seriously injured and believed the offender had left the mall.

The Woolworths at the mall was closed off to access, she said. Reports were much of the rest of the mall was open.

A spokesperson for Woolworths confirmed to RNZ this evening that the incident had occurred in its supermarket. All the staff were safe, the spokesperson said.

Another witness said the attack was sudden.

"I couldn't really see her face but definitely from assumption she must have been so frightened.

"It must have just hit her out of nowhere because honestly I'm not sure what her relationship was to the people who attacked her, or if it was just some random attack but that must have been so terrifying."

Hato Hone St John said it responded just before 5pm with four vehicles, including a road ambulance, and has taken one patient in serious condition to Tauranga Hospital.

One person took to social media to say she was locked down in a salon near the Countdown in Bayfair Mall due to a stabbing.

She said she could see police running through the mall with guns, as well as ambulance staff in attendance.

"Omg locked in the salon due big stabbing incident in Count Down next door in Bayfair Mall," one person reported on social media.

"Cops running round with big guns and other police and ambos here."

In her post she said it was hard to believe an incident like this was happening in Mount Maunganui but such stabbings were happening now around the world.

Another witness said they had seen more than six police cars speeding towards Bayfair.

Police told RNZ that armed officers responded as a precaution.

A store worker said the mall has been very quiet since the incident.

The worker, who didn't want to be identified, said she didn't see what happened but was told by mall security that someone had been injured in the supermarket.

She said stores were choosing to close early this evening, and the security team were regularly checking in.

The staffer said police were also visible, and while she personally felt reassured, some of her colleagues were worried.