Declan McCullagh/CNET

Amazon is investigating reports of employees leaking confidential internal data and offering other services to sellers on its e-commerce platform in exchange for bribes, the Wall Street Journal reported Sunday.

Employees at the internet retailer are allegedly selling sales and search information to independent merchants selling products on the site, giving them an edge over competitors in violation of company policy, the newspaper reported. Brokers working as intermediaries for Amazon employees are also offering to delete negative reviews and restore banned accounts, the newspaper said, citing anonymous sellers, brokers and others familiar with the probe.

The investigation began in May after the company was tipped off to the practice taking place in China, where it's said to be most prevalent, the Journal reported.

The reports of bribery are the latest challenge Amazon faces in protecting the integrity of its marketplace after working for years to eradicate its sites of fake reviews and counterfeit products. Since 2015, the company has been filing legal actions to fight against scams and already sued more than 1,000 entities involved in allegedly creating fake product reviews on its sites.

Middlemen working for sellers in China who want negative reviews of their products deleted use the messaging service WeChat to identify and approach Amazon employees who want to perform the service in exchange for cash payments from around $80 to more than $2,000, the newspaper reported.

Amazon confirmed the investigation's existence Sunday afternoon.

"We hold our employees to a high ethical standard and anyone in violation of our Code faces discipline, including termination and potential legal and criminal penalties," Amazon said in a statement. "In addition, we have zero tolerance for abuse of our systems and if we find bad actors who have engaged in this behavior, we will take swift action against them, including terminating their selling accounts, deleting reviews, withholding funds, and taking legal action."

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Originally published Sept. 16, 2018 at at 10:33 a.m. PT.

Updated at 12:30 p.m. PT with Amazon's statement.

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