A consumer watchdog has launched a probe into the sale of fake product reviews which it fears could mislead shoppers.
Instagram, the social media site, has removed 76 user accounts which were being used to trade, or facilitate the trade of, such reviews after pressure from the Competition and Markets Authority (CMA).
This follows similar action taken in January by Facebook, the owners of Instagram, and online auction site eBay.
The CMA began work on the issue last summer and yesterday launched an investigation to determine whether several major websites are doing enough to protect shoppers.
It is particularly concerned about how sites approach reviews which have been paid for and whether firms are manipulating the presentation of reviews by combining positive reviews of one product with reviews for another.
The regulator is not currently alleging that any firm has broken the law, but said it would take court action if necessary if its investigation uncovers any wrongdoing. The firms involved could be named at that stage.
Andrea Coscelli, the watchdog’s chief executive, said most people read online reviews before buying products or services.
He added: “It’s really important that the online reviews we read are genuine opinions. If someone is persuaded to buy something after reading a fake or misleading review, they could end up wasting their money on a product or service that wasn’t what they wanted.”
In addition to removing the accounts, Instagram has agreed to regularly monitor for profiles involved in trading fake reviews and to ensure measures are in place to remove the offending accounts.
The CMA said: “The CMA is not alleging that Facebook, eBay or Instagram intentionally allowed this content to appear on their websites.”
Ebay said it is committed to cooperating with the CMA on tackling fake reviews.
Neena Bhati, head of campaigns at consumer group Which?, said: "Online platforms must take greater responsibility for helping to prevent users from being duped by fake reviews and today's announcement should serve as a warning to companies that are failing to crackdown through a lack of proper oversight.”