Staff and shoppers were forced to evacuate Countdown Hastings after a person with a knife entered the store on Friday afternoon.
A police spokeswoman said the incident was reported about 2.13pm.
"It appears a person has entered the store on Queen St West and been approached by a member of staff, due to displays of anti-social behaviour," the spokeswoman said.
"The person is then reported to have been seen carrying a knife around the store before exiting."
The spokesperson said a member of the public confronted the person outside the store before the police arrived and the person was taken into custody.
There were no reports of anyone being threatened or injured.
It is understood the store closed of its own accord and staff have been allowed back inside.
A shopper who spoke to Hawke's Bay Today said she was at the counter with her children when shoppers were asked to evacuate the store.
"We were at the checkout and the alarm went and everybody just rushed, but it went pretty good coming out.
"We were at the door and we saw patched gang members coming out and standing there and screaming and swearing 'f*** off' and 'I'll kill you'."
A shopper said she had just arrived in the carpark when she witnessed the police chasing someone.
"I saw a chase with the police going around and around the carpark. There were sirens and then there was silence."
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