Wild scenes have emerged at Woolworths and Coles stores in Canberra less than an hour after it was announced the Australian Capital Territory would be entering a snap lockdown.

Canberrans will only be able to leave home for five essential reasons from 5pm on Thursday, Chief Minister Andrew Barr confirmed just before noon on Thursday. The lockdown will last for seven days.

Just minutes after revealing an infected man in his 20s had been in the community for three days, health officials said they had already heard reports of panic buying at supermarkets.

Shocking footage posted to Twitter shows massive crowds of people at Woolworths and Coles stores with baskets and trolleys brimming with items.

Several seem to be holding packs of toilet paper — a much sought-after item during the coronavirus pandemic.

Many can be seen not wearing masks despite standing close together.

Sky senior political reporter Jonathan Lea captured some of the wild scenes at Coles in Manuka, which has been deemed a Covid exposure site.

“The fevered madness of Manuka as Canberra goes Covid cuckoo,” he captioned the footage of stripped shelves and dozens of people waiting in a line that wraps around the store.

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Viewers were quick to call out people pictured for not wearing a face covering.

“Let's not have panic buying create a super-spreader event,” one man said.

“And a lack of masks…these folks are not thinking straight,” another wrote.

“The absence of masks may be more disappointing than the stockpiling,” a third chimed in.

“Canberra is really bad at the masking unless specifically told. I'll often be one of only a handful of people at the shop masked up,” a woman who appears to live in the ACT Tweeted.

On Monday, Woolworths announced it was limiting toilet paper to two packs per customer, per shop in the ACT, NSW, VIC, Cairns, Yarrabah LGA and south east QLD stores.

Yahoo News Australia has contacted Coles to inquire if any product limits are in place.

Coles staffer's kind act for shoppers

A staff member at one Coles store in Canberra was photographed handing out chocolates to those waiting in line.

Most people appeared to be wearing masks - as was the employee - as she offered Favourites to those waiting to enter.

"Look after each other," the person who took the photo wrote on Twitter.

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