Protestors are stepping up their campaign against Amazon with a demonstration at Bluewater claiming the online retail giant hiked up prices during the pandemic.
Critics have been outside the shopping centre in Greenhithe, near Dartford and are taking the fight to authorities to "expose price gouging".
The Unite union members staged the protest this morning at Bluewater and on the promenade in Gravesend after submitting a formal complaint to the Competition and Markets Authority (CMA).
It claims Amazon "abused its market position" at the height of the Covid-19 crisis by inflating prices for those who relied on home deliveries.
But the retailer says it has worked with the CMA throughout the pandemic to ensure listings on its marketplace with inflated prices were taken down.
Amazon said it also worked with the regulator to make sure prices on its own store were fair and correct.
Unite says it has conducted research which it says "uncovered compelling evidence of price gouging throughout 2020".
The union claims 50 different items were identified as being sold on Amazon for "at least double their usual price" between March and November last year.
It says these items include soap, antibacterial spray and wipes, washing up liquid, hand wash, bleach, thermometers, face masks, toilet paper, disposable gloves, sanitary products, vitamins, toothpaste, sudocream, tea and tinned food.
A listing for Carex antibacterial hand lotion usually priced at £1 was found in March to have increased to £26.41 while a Braun digital thermometer increased from £39.99 to £149.99.
It is calling on Amazon to repay overcharges paid by consumers.
The protests, which will take place across the country, come as part of Unite's ongoing campaign called Action on Amazon and will also highlight "poor working conditions and anti-trade union tactics".
It wants Amazon bosses to agree to a "declaration of neutrality" which would recognise workers' rights to join unions.
Sharon Graham, Unite executive officer for organising and leverage said: “Amazon is steeped in corporate irresponsibility, from its anti-union tactics to tax avoidance.
"Now Amazon stands accused of profiting from price gouging on its website at the height of the pandemic when vulnerable people were most at need. It's time for Amazon to be held to account."
An Amazon spokesman said: "“There is no place for price gouging on Amazon. We worked with the CMA more than a year ago to stop attempts by some sellers to take advantage of the global health crisis.
"Our action at the time was clear and decisive - we removed the offers referenced in this complaint and terminated seller accounts.
"We continue to monitor our store 24/7 to remove offers that violate our policies."
A CMA spokesman said: “We have received the letter from Unite the Union and will be considering it carefully.”
The regulator has worked with multiple retailers during the pandemic to ensure fair pricing of items is followed.
It confirmed it written to Amazon regarding complaints of "price gouging" and the online retailer had taken steps to address listings for essential items which had been inflated.
The body also worked with eBay to ensure similar rules were followed.
The CMA investigated four pharmacies and convenience stores last year over complaints of hiking prices for hand sanitiser products.
All four investigations were closed after the CMA ruled there had not been a breach of competition law.