Amazon.com Inc haslaunched an internal investigation in India after a whistleblower alleged an employee had taken kickbacks, a source with direct knowledge of the case told Reuters.

Indian news outlet Morning Context on Monday cited three sources who said Amazon had begun an investigation following a complaint.

Amazon did not answer Reuters’ questions related to the investigation involving its India unit but said in a statement that it has “zero tolerance” for corruption.

“We take allegations of improper actions seriously, investigate them fully, and take appropriate action. We are not commenting on specific allegations or the status of any investigation at this time,” a spokesman said.

The source told Reuters that Amazon has been investigating the matter for about two months after a complaint was received about the dealings Amazon India legal team employee, Rahul Sundaram, had with outside counsel working for the firm.

Sundaram, in response to Reuters request for comment, referred questions to Amazon. He has been sent on leave by Amazon pending the investigation, the source said.