Members of the public have shared their frustrations after a picture of an overflowing coronavirus test drop-off box in Sutton was posted online.

Teaching assistant Gavin Marshall captured an image yesterday of a drop-off point run by testing firm Randox.

He expressed his anger at being “forced to pay Randox over the odds” for a day two PCR, only to find the drop-off point “overflowing and insecure”.

Tilly Slight, who works in the art sector in London, replied on Twitter to Mr Marshall’s photo with the message “You think that one’s bad?”.

She uploaded an image of a full Randox box with dozens of test kits stacked on top.

Another Twitter user, with the account @tothepoint2019, posted an image of a pair of packed drop boxes.

He described the situation as an “absolute joke”, and claimed the tests “mean nothing apart from ££££ in an MP’s best mate’s pocket”.

He added: “You don’t even have to do the test, just need the reference number for the Passenger Locator Form. Buy the cheapest you can find!”

Paul Charles, chief executive of travel consultancy The PC Agency, said the images demonstrate “the absolute mess that PCR testing has become”.

Mr Charles claimed they are proof that private laboratories “aren’t in any hurry to turn around the results” and warned that personal details and samples are being “left for anyone to take”.

A spokesman for Randox said: “Randox is constantly expanding and improving its Covid-19 testing capacity and associated logistics network, which is already the largest in the United Kingdom, to meet the rapidly growing demand resulting from the loosening of travel restrictions.

“Randox continues to increase the number of drop boxes across the United Kingdom, which already totals over 200, and is increasing the frequency of box collections which are already occurring multiple times per day.

“Randox is providing premium testing services in dynamic and rapidly changing circumstances and is committed to continuously improving its logistics network, to ensure that international travellers receive their results in time.

“All of the sample kits pictured will be processed.”

International travellers entering the UK must pay for a PCR test on or before the second day.

These typically cost around £50, but some are priced at more than £100.

People who are not fully vaccinated must take a second test on or before day eight if they have arrived from an amber list country, or are staying in a quarantine hotel.

This group must also self-isolate at home for 10 days after arrival.

They can leave quarantine early if they receive a negative result from an additional test after at least five days.

But many people have reported delays in receiving pre-ordered test kits, meaning they must stay at home for longer than planned.

Health Secretary Sajid Javid has asked the competition watchdog to investigate the market for travel PCR tests in response to concerns about the cost for families travelling abroad.