Pictures show a long line of people around the car park of a Tesco in south London at 6am on Saturday, just to buy essential goods during the coronavirus pandemic.
Many supermarkets have set earlier hours of operation aside for the elderly and key workers, but there are signs they too are struggling to buy what they need, as people worried about COVID-19 stockpiling.
Prime minister Boris Johnson has spoken to supermarket bosses about efforts to keep supplies flowing and how to overcome the panic buying that is gripping the UK.
Shelves have been stripped of essential items, such as toilet rolls, hand sanitiser, paracetamol, meat, fruit and vegetables as shoppers ignore pleas not to stockpile.
Tesco, Marks & Spencer, Sainsbury's and Asda have announced a golden shopping hour for NHS and social care workers, so they can join older and vulnerable shoppers in having less competition for restocked shelves.
Stores have said they are taking on thousands of temporary and permanent workers to deal with the increased demand.
Environment Secretary George Eustice urged people to "be responsible" when shopping and to "think of others."
"Buying more than you need means others may be left without," he said.
"There is more than enough food to go round and our food supply chain is able to expand production to cope with increased demand," he added.
"Be responsible when you shop and think of others.
Mr Eustice said that it was for retailers to agree what the appropriate limit was on goods such as toilet paper.
A queue ran along the entire length of the Tesco car park in New Malden, southwest London on Saturday morning.
Drone footage showed shoppers waiting in line for the superstore to open, appearing to space themselves out to ensure they kept the recommended distance.
Another picture obtained by Sky News was taken outside a branch of Iceland in Wallington, also southwest London, where a special shopping session for key workers had been laid on.
Many of those key workers who had turned up to be able to buy food and essentials were unable to get in and had to go elsewhere.
The teacher who took the picture said it was a "very strange sight".
She told Sky News: "I thought it would be much quieter as the shop was just open to target groups and I was pretty disappointed because I was only shopping for food bank bits and pieces."
There were reports of people having to spend several hours trying to buy things they needed, and to visit several stores.
Long queues have also been reported at several branches of Costco, as people appear to switch from supermarkets to wholesalers in a bid to stock up.
It comes a day after a photo emerged of a paramedic staring at completely empty shelves in a Sainsbury's, said to be in south London.
Critical care nurse Dawn Bilbrough, from York, also appeared in a social media video making a heartfelt plea for shoppers to stop stockpiling.
In the video, she is seen crying after visiting a supermarket following a 48-hour hospital shift to find there were no fruit or vegetables - a scene that has been mirrored across the country.
Mr Johnson has spoken to the leading supermarket chains to see what can be done to ensure shelves remain stocked and the supply chains can cope.
The aim is to help around 1.4 million people with underlying health conditions who will be asked in the coming days to quarantine themselves for their own safety.
Meanwhile, Sainsbury's is following other supermarket chains and introducing a golden shopping hour for NHS and social care workers, after earlier in the week it and others launched a separate shopping hour for the elderly.
Sainsbury's says health care workers will be able to shop between 8am and 9am every Monday, Wednesday and Friday, alongside elderly and vulnerable shoppers.
However one NHS worker immediately tweeted the supermarket saying: "As a NHS worker who will have regular contact with patients who have coronavirus, I'm trying to minimise my contact with vulnerable groups.
"I appreciate the gesture, but I do not feel that I can shop at the same time as the elderly. Please consider separate shopping hours for us!"
Meanwhile, Morrisons said it was taking on up to 500 staff from Marie Curie and CLIC Sargent charity shops to help the elderly and vulnerable in its supermarkets.
And to thank NHS workers and community groups for their hard work, Lidl said it was giving away thousands of bouquets of Mother's Day flowers.
In an attempt to deal with the unprecedented demand for hand sanitiser, and the consequences of the closure of pubs and subsequent cut in demand for beer and spirits, some brewers have switched their operations to make alcohol-based hand sanitiser.
North-east Scottish brewers Brewdog are producing an alcohol based gel called Brew gel.
A number of small gin distilleries across Britain are also producing hand sanitiser.
Meanwhile, eBay has announced it is heavily restricting the sale of face masks and hand sanitiser products.
Sky News revealed two weeks ago that some sellers were charging exorbitant prices, exploiting shortages after panic buying.
eBay said only a whitelist of trusted sellers will be permitted to continue trading these items at appropriate prices.