The FBI investigation that led to the resignation of CIA Director David Petraeus started with a complaint several months ago that Paula Broadwell, his biographer, was sending harassing emails to a third person, a U.S. official told The Associated Press.
FBI agents discovered exchanges between Broadwell, a West Point graduate and Army Reserve officer, and Petraeus, the retired four-star general who commanded troops in Iraq and Afghanistan, according to the official.
Investigators said the emails raised the possibility of security breaches that needed to be addressed directly with Petraeus because his emails in the matter were in most instances from a personal account, rather than his CIA one.
Details about the third person were not immediately available.
The official was not authorized to publicly discuss about the investigation and spoke about the probe only on condition of anonymity.
The sudden and unexpected end of a career that many thought might culminate in a run for the presidency came on Friday. Petraeus tendered his resignation, which President Barack Obama accepted.
Petraeus’ deputy, Michael Morell, will serve as acting director, Obama said. Morell was the key CIA aide in the White House to President George W. Bush during the terrorist attacks of Sept. 11, 2001.
The change in leadership is taking place as the administration and the CIA struggle to defend security and intelligence lapses before the Sept. 11 attack that killed the U.S. ambassador to Libya and three others Americans. It was an issue during the presidential campaign that ended with Obama’s re-election Tuesday.
Petraeus turned 60 on Wednesday.
The retired general told CIA employees in a statement that he was guilty of “extremely poor judgment” in engaging in the affair. “Such behavior is unacceptable, both as a husband and as the leader of an organization such as ours.” He said he had offered his resignation to Obama on Thursday and the president accepted it Friday.
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Administration officials said the White House was first notified about the Petraeus affair on Wednesday, the day after the election. Obama, who returned to the White House that evening after spending Election Day in Chicago, wasn’t informed until Thursday morning.
For the director of the CIA, being engaged in an extramarital affair is considered a serious breach of security and a counterintelligence threat. If a foreign government had learned of the affair, the reasoning goes, Petraeus or Broadwell could have been blackmailed or otherwise compromised. Military justice considers conduct such as an extramarital affair to be possible grounds for court-martial.
Failure to resign also could create the perception for the rank and file that such behavior is acceptable.
Petraeus, who became CIA director in September 2011, was known as a shrewd thinker and hard-charging competitor.
In the preface to “All In: The Education of General David Petraeus,” published by Penguin in January, Broadwell said she first met Petraeus in the spring of 2006. She was a graduate student at the Kennedy School of Government at Harvard, and he was visiting the university to discuss his experiences in Iraq and a new counterinsurgency manual he was working on.
In 2008, she wrote, she was pursuing a Ph.D. in public policy and embarking on a case study of Petraeus’ leadership. After Obama put Petraeus in charge in Afghanistan in 2010, Broadwell decided to expand her research into an authorized biography.
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Broadwell made many trips to Afghanistan, with unprecedented access to Petraeus, and also spent time with his commanders across the country. When Petraeus took the job at the CIA, she remained in close contact with him, sometimes invited to his office for events like his meeting with Hollywood actress Angelina Jolie.
With the book done, she told friends she had been concentrating on turning part of her research on Petraeus into a dissertation, to complete her doctorate.
Petraeus, in his email, told his CIA employees that he treasured his work with them “and I will always regret the circumstances that brought that work with you to an end.”
Other CIA directors have resigned under unflattering circumstances. CIA Director Jim Woolsey left over the discovery of a KGB mole, and John Deutch left after the revelation that he had kept classified information on his home computer.
Before Obama brought Petraeus to the CIA, Petraeus was credited with salvaging the U.S. war in Iraq.
President George W. Bush sent Petraeus to Iraq in February 2007, at the peak of sectarian violence, to turn things around as head of U.S. forces. He oversaw an influx of 30,000 U.S. troops and moved troops out of big bases so they could work more closely with Iraqi forces scattered throughout Baghdad.
Petraeus’ success was credited with paving the way for the eventual U.S. withdrawal.
After Iraq, Bush made Petraeus commander of U.S. Central Command, overseeing all U.S. military operations in the greater Middle East, including Afghanistan and Pakistan.
When the top U.S. commander in Afghanistan, Gen. Stanley McChrystal, was relieved of duty in June 2010 for comments in a magazine story, Obama asked Petraeus to take over in Kabul and the general quickly agreed.
In the months that followed, Petraeus helped lead the push to add more U.S. troops to that war and dramatically boost the effort to train Afghan soldiers and police.
Morell had served as deputy director since May 2010, after holding a number of top roles, including director for the agency’s analytical arm, which helps feed intelligence into the president’s daily brief. He also worked as an aide to former CIA Director George Tenet.
Read more: TIME MAGAZINE