The FBI is reportedly coordinating with Hillary Clinton’s campaign schedule in order to find a time to interview the presidential candidate about her private email server, CNN reports.

Investigators have already interviewed several of Clinton’s top State Department aides, including Huma Abedin, the network reported on Thursday. Some of those aides have been interviewed several times.

The next step in the investigation — which is looking into whether any classified information was mishandled on Clinton’s server — will be to interview Clinton herself.

But that poses a problem because she is in the heat of a presidential campaign. And with reporters constantly following the former secretary of state, it will be hard for FBI agents to interview her without attracting attention.

CNN reports:

The fact that Clinton is a presidential candidate active on the campaign trail presents some logistical challenges for the FBI, which has been quietly bringing witnesses into an FBI office without drawing attention. Clinton’s security is provided by the Secret Service and she’s typically followed by a corps of campaign reporters. The FBI plans to coordinate her interview with her attorneys and security to try to ensure it can be done privately.

According to federal law enforcement sources, the investigation has yet to uncover evidence that Clinton willfully violated the law.

That does leave open the possibility that Clinton compromised classified information through negligence, which could constitute a federal crime. Clinton hired Bryan Pagliano, a former campaign worker, to manage her private email server. He has been interviewed by the FBI as well. He exchange his cooperation for immunity sometime last year.

[dcquiz] CNN also reports that investigators have found no evidence to support claims made by a Romanian hacker known as Guccifer that he hacked into Clinton’s email server. The hacker told Fox News and NBC News that he hacked into Clinton’s server in 2013, after she left the State Department. He was recently extradited to the U.S. and faces nine charges for various alleged cyber crimes.

Republican National Committee chairman Reince Priebus responded to the news, saying it “underscores just how big of a risk a Hillary Clinton presidency truly is.”

“These FBI interviews are another reminder of the gross negligence Hillary Clinton displayed as Secretary of State when she set up an off the books email server that exposed classified information on thousands of occasions,” he said in a statement. “This reckless attempt to skirt government transparency laws put our national security at risk.”

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