A prominent hacker tells Fox News’ James Rosen that Hillary Clinton appears to have established multiple email addresses for private use.

Aides to the former secretary of state say she only used one private email while in office – hdr22@clintonemail.com. That domain name has been traced to a private Internet server in Clinton’s hometown of Chappaqua, N.Y. The server was registered in the name of Clinton’s former aide Eric Hothem a week before the Obama administration assumed office.

Rosen’s hacker source employed a tool called “The Harvester” to search a number of data sources to look for references to the domain name Clintonemail.com. The source says it appears Clinton established multiple email addresses, including hdr@clintonemail.com, hdr18@clintonemail.com, hdr19@clintonemail.com, hdr20@clintonemail.com, and hrd21@clintonemail.com.

Other email addresses include h.clinton@clintonemail.com, Hillary@clintonemail.com, contact@clintonemail.com, and mau_suit@clintonemail.com.

It’s not clear whether Clinton used any or all of these email addresses. It’s also unclear whether her aides used them.

Fox News reached out to the Clinton team for comment and has not heard back.

Watch Rosen’s report on “The Kelly File” above.

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