A woman prompted an angry backlash after trying to sell lateral flow kits online.
She posted a message in a community Facebook group in the Stoke-on-Trent area, boasting that she had 'large quantities' of kits available.
Demand for tests is particularly high following a rise in Omicron cases, and Boris Johnson is urging people to take a test before meeting up with friends and family, or returning to work.
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The woman offered to sell the tests for £10, and even promised to guarantee next day delivery.
Her post - which was screenshot and sent to StokeonTrentLive - sparked an angry reaction from other people. She has since been banned from the group.
The profiteering ploy was rumbled as thousands of Brits have struggled to find rapid tests after the Christmas period as the nation prepares to return to work and school this week.
Some sellers have been caught trying to flog lateral flow tests for £100 on eBay and marketplace sites in an attempt to make a quick buck.
Despite the sale of such kits being prohibited on these sites, some sellers are trying to get around the rules.
Conservative MP Nigel Mills said: "It is a disgrace that some people would try to exploit a national shortage of tests as a way to make money.
"The online websites and any auction houses should refuse to list the tests for sale.”
The UK Health Security Agency has announced eight million kits will be made available to pharmacies - but many appear to be finding their way online to be sold for profit.
And Health Minister Edward Argar has also moved to reassure the public orders have been ramped up.
He added: "Tests are available. We advise people to keep going on the website to refresh it and they will find that every hour more slots are available for booking one for delivery or for collecting from pharmacies.
“We’ve ramped up supply to reflect that and you’ll continue to see that supply increasing in the coming weeks.”
The Omicron variant sparked countrywide test shortages and delays throughout December.
Its rapid spread could leave up to 1.4 million public sector workers absent, with nearly one in 10 NHS staff already off work at New Year.
