A Romanian computer hacker who unveiled the existence of Hillary Clinton’s private email server she used while secretary of state pleaded guilty to hacking-related offenses on Wednesday.br Marcel Lazar, who used the alias “Guccifer,” entered his guilty plea in U.S. District Court.br Sentencing was set for September 1.br In recent media interviews, Lazar claimed he easily hacked into Clinton’s controversial server.br But, the Justice Department nor investigators confirmed this claim.