In a recent blog post, Amazon accused social media companies of not doing more to prevent the spread of fake reviews.

Fake Amazon reviews are often purchased and sold on social media platforms like Facebook.

While Amazon said that “some” of the companies had improved their responses to the company’s fraud reports, the company said it wanted social media companies to find and remove fraud before reporting it to them.

According to Amazon, its own “continued improvements in detection of fake reviews and connections between bad-actor buying and selling accounts leading to an increasing trend of bad actors attempting to solicit fake reviews outside Amazon, particularly via social media services. While we appreciate that some social media companies have become much faster at responding, to address this problem at scale, it is imperative for social media companies to invest adequately in proactive controls to detect and enforce fake reviews ahead of our reporting the issue to them.”

For more information, read the original story in Arstechnica.