Justin Cooper, the aide who managed Hillary Clinton's email server during her time as secretary of state, earned $127,200 in annual salary from the Clinton Foundation, emails published by WikiLeaks on Friday show.

Cooper was hired by the foundation as a "senior adviser" in 2009, the same year Clinton joined the State Department. Multiple witnesses told the FBI Cooper served as the main point of contact for issues with the private server in Clinton's basement as they arose during her tenure.

A second aide, Bryan Pagliano, also provided maintenance and support for "clintonemail.com" users. While Pagliano was employed directly by the State Department, he also reportedly pocketed a paycheck from Clinton for his work on the email network. It is unclear whether that money came out of the Clinton Foundation or from the Clintons' own wallet.

The email was included among the 25,000 emails published as of Friday by WikiLeaks from the inbox of John Podesta, Clinton's campaign chair. An unidentified hacker obtained the emails illegally. U.S. intelligence agencies suspect the hackers have ties to Russia.

Cooper appeared before the House Oversight Committee last month to testify about his involvement in the set-up and operation of the server in Clinton's basement. He was also interviewed by FBI agents in the course of their year-long investigation of Clinton's treatment of classified material.

The Clinton Foundation presented many potential conflicts of interest for Clinton and her staff during their four years at the State Department, from donors seeking and securing favors to Clinton aides accepting duel employment at both the foundation and the agency. The fact that Cooper took such generous payments from the foundation while working on Clinton's email server raises additional questions about the extent to which charity activities overlapped with State Department work.