Amazon has fired several employees in the United States and in India in an attempt to stop data leaks and bribes within the company.

The employees allegedly inappropriately accessed company data misused by independent merchants, people familiar with the Amazon’s investigation told The Wall Street Journal.

Amazon also has deleted thousands of reviews, restricted seller access to customer data on its website, and managed to stop some techniques that trick the site into surfacing products higher in search results, according to the report.

Evidently efforts have not stopped sellers from sabotaging rivals. During the busiest shopping time of the year, some merchants claim that competitors are maliciously flagging products as counterfeit or infringing trademarks. This harassment has prompted Amazon to temporarily ban legitimate products from the site.

Some products are being classified in other categories. For example, one merchant said his home decor products — such as a throw pillow with a sequined mermaid on it — were declassified as an adult product and no longer served up in Amazon searches.  

Janel Laravie, founder at Chacka Marketing, hasn’t come across any such activity, but in an email to Search Marketing Daily wrote that “it seems too possible to not be true.”

To make matters worse, reports the WSJ, sellers are buying Amazon wholesaler accounts on the black market to gain access to volumes of product listings. The Amazon accounts are designed to enable wholesalers to edit product listings to ensure they are marketed accurately. Sellers say rivals are conducting malicious activity like changing photos to unrelated items.

In fact, the WSJ reports that Chinese firms sell wholesale vendor accounts for about $15,000 or rent them for up to $1,500 per month.

In another instance, sellers engage in a practice dubbed “brushing” where fake accounts use real addresses to place orders so they can leave positive reviews.