WASHINGTON – The Federal Bureau Investigation (FBI) on Saturday interviewed Democratic presidential hopeful Hillary Clinton at its headquarters in Washington, casting doubts on whether the former Secretary of State will be able to make history as America’s first female president in the upcoming November elections this year.

The interview, which lasted three and a half hours, was part of an ongoing investigation into her use of a private email server for official communication while she was secretary of state from 2009 to 2013.

In an interview with MSNBC, Clinton claimed that she was happy to have been interviewed by the FBI, adding that she had volunteered for it.

“I have been answering questions about this issue for over a year,” she said, adding that she was ready to address the issue at any forum.

Clinton’s interview came on the back of the FBI’s other interviews with her former staffers, including top aide Huma Abedin.

It is still clear whether Clinton’s interview marks a conclusion to the investigation or not.

Meanwhile, Clinton’s likely opponent in the presidential race, Republican Donald Trump expressed his views about the investigations on Twitter, saying that it was “impossible” for the FBI not to recommend criminal charges against his opponent.

In another tweet, he also dubbed the system as rigged, reacting to the recent meeting of Clinton’s husband, former President Bill Clinton, and Attorney General Loretta Lynch.

He continued in this vein in a separate tweet saying, “It was just announced-by sources-that no charges will be brought against Crooked Hillary Clinton. Like I said, the system is totally rigged!”.

Hillary Clinton is set to be formally nominated by the Democrats as a candidate for the November 8 presidential election at the party’s forthcoming convention later this month.

The FBI is investigating whether Clinton’s move to run a private email server for official communication had jeopardized the security of classified information or not. Any finding against her could lead to problems for her presidential campaign.

Several hundred emails of Hillary Clinton have so far been released by the State Department on the directions of the Supreme Court. She also faced an hours-long hearing at the Senate for her actions.