Hillary Clinton purchased some of the BlackBerries she used as secretary of state on eBay, Utah Rep. Jason Chaffetz said on Wednesday.

“That’s what she liked, so she did it. It creates this huge vulnerability. And it’s unnecessary,” Chaffetz, who chairs the House Oversight and Government Reform Committee, said during a forum hosted by the American Enterprise Institute.

The forum was held to discuss last year’s hack of the Office of Personnel Management.

“I don’t want to get into this too much, but part of what was happening with the secretary of state is, she was acquiring technology that wasn’t even supported by BlackBerry. You couldn’t buy it. She was actually buying this stuff off of eBay because somebody was selling their old machine,” Chaffetz said.

Clinton used at least eight different BlackBerries while in office, according to the FBI’s email investigation report, released last week. None were provided by the State Department. In contrast, Clinton’s circle of aides and all other State Department employees used a government-issued device.

[dcquiz] When Clinton first took office, she requested a government BlackBerry similar to one that the National Security Agency built for President Obama. But when the request was rejected, she continued using a private device that was hooked up to her private email server.

The State Department made other offers to provide Clinton with agency-issued hardware later in her tenure, but was rebuffed.

Neither Clinton nor her attorneys were able to provide old BlackBerries to federal investigators. It is unclear where they went, though one aide to Bill Clinton told investigators that he smashed at least two of the devices with a hammer.

It is also unclear exactly how Clinton’s purchase of used BlackBerries put her communications at greater risk. Some of those questions may be answered in House hearings scheduled for this week and next. Chaffetz’s committee is holding a hearing on Thursday regarding the State Department’s handling of Freedom of Information Act requests. And next week, FBI director James Comey is slated to testify in front of the House Judiciary Committee.

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