Current and former US intelligence officials say the FBI still has an open investigation into whether David Petraeus improperly provided highly classified documents to a mistress. The case has been open since 2012, when he resigned as CIA director.

While the FBI was investigating an unrelated email cyber stalking complaint, they discovered David Petraeus’ extramarital affair with Paula Broadwell, his biographer. Though that discovery led to Petraeus’ resignation, the FBI still has an open investigation into whether Petraeus improperly provided highly classified documents to Broadwell. The unauthorized material was found on Broadwell’s personal computer.

“It was inappropriately shared and it should never have been shared,” one former senior intelligence official told Bloomberg News.

READ MORE:CIA tries to crack down on harassment, leaves employees unhappy

The FBI cleared Broadwell of the cyber stalking charges. Yet two US officials familiar with the investigation said she was never authorized to receive the classified documents found on her computer because “it included compartmentalized intelligence that only a handful of very senior officials were approved to view,” according to Bloomberg News.

That breach in the eyes of the FBI is a serious matter despite President Obama saying Petraeus never endangered national security.

At the time of the investigation in 2012, both Petraeus and Broadwell denied to investigators that he was the source of any classified information, officials said.

READ MORE:Ray McGovern describes brutal arrest at Petraeus event (VIDEO)

Since the scandal broke, the former general began working with private-equity firm KKR, and has academic posts at Harvard and the University of Southern California. Still, White House sources told Bloomberg that the Obama administration has sought his advice on the fight against the Islamic State, and still has his security clearance.

“All of us who know him and are close to him are mystified by the fact there is still this investigation into him,” said Jack Keane, a retired four-star US Army General, and an adviser and mentor to Petraeus.

READ MORE:Socialite entwined in Petraeus scandal sues Pentagon

Keane questions whether the ongoing investigation may be driven by something other than a desire to investigate a potential crime. “It makes you wonder if there is another motivation to drag an investigation out this long,” he said.

READ MORE:CIA classified review: Covertly arming insurgents doesn’t work

Rep. Jason Chaffetz (R-Utha), the incoming chairman of the House Committee on Oversight and Government Reform, said the investigation needs to end if there are no charges coming.

“If he has done something wrong, charge him, if he has not, let him go,” he said. “At this point I don’t know what their motivation is. But I worry they will let this linger until the President leaves office.”

Rep. Jason Chaffetz (R-Utha), the incoming chairman of the House Committee on Oversight and Government Reform, said the investigation needs to end if there are no charges coming.

“If he has done something wrong, charge him, if he has not, let him go,” he said. “At this point I don’t know what their motivation is. But I worry they will let this linger until the President leaves office.”