Amazon has started legal action against more than 1100 people for allegedly posting fake reviews on its website. The online retail giant said in its lawsuit, filed in a state court in Seattle on Friday, that the defendants had "tarnishing Amazon's brand for their own profit and the profit of a handful of dishonest sellers and manufacturers".

Amazon says the defendants - all referred to as 'John Does,' as the company only knows their usernames - advertised their false review services through website The defendants charged as little as $5 to write positive reviews and give five-star ratings to products.

"While small in number, these reviews can significantly undermine the trust that consumers and the vast majority of sellers and manufacturers place in Amazon, which in turn tarnishes Amazon's brand," the company said in its complaint.

Amazon said it carried out an "extensive investigation" of the defendants, which included purchasing fake reviews from them. It is alleged that many of the John Does attempted to avoid detection by using multiple accounts from unique IP addresses.

A large number of the defendants allegedly offered to place a 'verified review' - which shows the reviewer has purchased the item - on the condition that they don't pay for it. Some did this by requesting voucher codes for the product so they could get it for free, while others asked the seller to send them an empty parcel in order to create a shipping record.

Amazon pointed out that Fiverr is not a defendant in the complaint and the online retailer does not hold the website responsible. Amazon did say, however, that Fiverr's take-down process did not address the "root cause of the problem" and is not a "sufficient deterrent" to stop other users of its site from offering fake reviews.

"Amazon is bringing this action to protect its customers from this misconduct, by stopping defendants and uprooting the ecosystem in which they participate," the lawsuit says.

The move comes after Amazon sued a number of websites in April for selling fake reviews. As the number of people offering this kind of illicit service increases, the company has started using its own Artificial Intelligence machine-learning system to root out fake product reviews and inflated star ratings.