Countdown Supermarkets has issued a public statement pleading with customers to "shop as you normally would", as the first images of long queues and panic buying emerge from Auckland.
"Over the next few hours, we'll be working to bring our Alert Level 3 measures into place in Auckland, and Level 2 measures throughout the rest of the country," Countdown Supermarkets posted on Facebook.
"This will include physical distancing in our stores, limits on customer numbers, limits on some products, queue control and extra cleaning and hygiene measures.
"We're well practiced in what needs to be done to keep our team and customers safe, and there's plenty of food and supplies for everyone. Please keep shopping as you normally would and there is no need to stock up. Look out for each other, and stay safe."
Despite pleas from Prime Minister Jacinda Ardern and Auckland Mayor Phil Goff to remain calm, late night shoppers swarmed to the few supermarkets still open in Auckland following the announcement that the city is heading into a three-day level 3 lockdown.
During tonight's announcement, Ardern urged New Zealanders to remain calm.
"Please do not rush to the supermarket tonight ... there is no reason to rush out and back any purchases this evening.
Pharmacies and supermarkets will remain open, but Ardern said there was no reason to panic-buy.
Auckland Mayor Phil Goff echoed the sentiment, calling for calm and patience as another lockdown looms over the city.
"I understand that people are probably feeling a little bit scared, a little angry and a little confused right now. None of us wanted to go back into a lockdown, but we always knew this was a very real possibility," he said.
"I am urging Aucklanders to come together like we did last time to stamp out community transmission. Please remain calm, please do not panic buy and please follow the lockdown rules."
And yet Countdown New Lynn was forced to close shortly before 10.30pm, an hour and a half early, after it was overrun by shoppers.
A witness told the Herald the line to the store stretched halfway down the New Lynn mall, with dozens of shoppers inside stockpiling staples including rice, bread and pasta.
Supermarket staff were passing out masks to other staff to keep them safe, but the witness had only seen two customers wearing masks.
Simon Oosterman told Newstalk ZB the line of eager shoppers stretched 2km from the Countdown New Lynn supermarket.
"I counted over 200 people in the line, there are cars literally queuing up outside because there aren't enough carparks."
Oosterman had been standing outside the supermarket for the past half hour and the queue hadn't yet budged, he said.
Countdown Lynfield has also closed early, a customer said.
A Greenlane shopper told the Herald he abandoned the idea of shopping at the supermarket when he saw queues snaking out the door.
"It was chaos. There was traffic blocking all of the roads leading to the supermarket, the parking lot was completely full and there were cars queued to get into the parking lot.
"There was already a queue snaking outside. I didn't think I'd even be able to get a park, let alone get the shopping done before the store closed."
No one appeared to be following physical distancing measures or wearing a mask at the store, he said.
Most Auckland supermarkets typically close at 10pm, but the Greenlane and Lynn Mall Countdown stores typically close at 12am.
"It was so instant, I was there probably around 9.50pm and there were people everywhere."
New World and Pak'nSave websites appeared to have crashed shortly after this evening's announcement, as thousands of shoppers rushed to stock up online.
Countdown's website also appeared to be experiencing issues as shoppers overwhelmed the site, warning of "very high demand" on its online shopping service.
Security staff were standing outside the Countdown Grey Lynn and the Countdown Ponsonby, neither of which will open until 6am.