Hillary Clinton paid a State Department staff member to maintain the private email server she used during her time as US Secretary of State, say reports.
The Democratic presidential front-runner has faced questions about transparency since it emerged in March she used a private email rather than a government-issued state.gov email address when she was America's top diplomat from 2009 to 2013.
The arrangement with IT specialist Bryan Pagliano helped Mrs Clinton maintain her personal control over the server and ensure taxpayers were not paying for its upkeep, The Washington Post said, citing an unnamed campaign official.
The server was also shared by her husband, former President Bill Clinton, and their former aides, it said.
Mr Pagliano this week declined to produce documents and testify before a House of Representatives committee about the server, invoking his Fifth Amendment rights against self-incrimination.
He was IT director for Mrs Clinton's 2008 presidential campaign and went to work for the State Department when she took up her Cabinet job.
The Post said the Clintons paid Mr Pagliano $5,000 for "computer services" before he joined the State Department in 2009, quoting a financial disclosure form he filed that year.
They continued to pay him to maintain the server while he was working for the State Department, The Post said.
Mr Pagliano reportedly did not list any outside income in the required personal financial disclosures he filed each year.
He left his IT job at the State Department in February 2013, the same month Mrs Clinton stepped down as secretary.
It is not known when or who 'wiped' Mrs Clinton's personal email server.
But it is believed to have happened after October 2014, when the State Department requested personal emails be returned as part of her business records.
Fox News, quoting an intelligence source, say FBI investigators are "confident" they can recover the deleted records.
Mrs Clinton has maintained she did nothing wrong, insisting she sent no information via email that was classified at the time, and received no material marked that way.
But the State Department said on Monday that about 150 more Clinton work emails have recently been designated as containing classified information.
No evidence has emerged that suggests her email activities harmed national security.
