Vector confirmed the major Auckland power outage has affected Epsom, Grafton, Parnell, Remuera and Newmarket.
The company is responding to a power outage "affecting parts of suburbs in central Auckland including Newmarket and Remuera," Vector said in a statement.
"A crew is onsite with another in transit. At this stage we are not able to confirm the cause.
"We thank those affected for their patience and encourage people to register for updates and follow progress on our website."
A Vector spokesman did not have information on how many customers were affected by the outage and was waiting for further updates.
Power went out at the Westfield Newmarket shopping mall. At around 2:20pm, a shopper told the Herald the power had just been restored and that congestion in the area was beginning to ease.
Earlier, one person at Westfield Newmarket said it was "like a sh** show with retailers and restaurants trying to work out how to deal with punters."
A man who was shopping at Countdown in the Westfield Newmarket mall said he saw lights flicker at 1.15pm.
"Retail staff were guarding their merchandise as stores rely on electronic doors."
Another shopper who was at the time eating in the on the top floor foodcourt of the mall said employees were collecting contact details of those eating as no payments could be made.
"The place is in darkness, food court in chaos."
Once power came back on, shoppers were returning to eateries to pay their bills.
A man at Timezone with his family said it was a "mad rush" inside the mall.
A spokeswoman for Westfield mall repeatedly refused to say whether the power was still on, saying only the mall remained "open and operational".
When pushed, she told the Herald all questions about the power outage would have to be directed to Vector.
Police are not taking any immediate action in relation to the power cut.
"Police are aware and are monitoring but at this stage it doesn't appear we are required to respond in any notable capacity. Police will respond if and as needed," said a spokesperson.