The emails to now-retired Marine Gen. James Mattis and others, warning them to stay away from a Tampa, Florida, socialite, led to the discovery of the affair and revelations that Petraeus had shown classified secrets to his lover, Paula Broadwell.
According to an FBI report and a U.S. official, agents interviewed Mattis, who said he always had proper interactions with the socialite, Jill Kelley. The official spoke on condition of anonymity because the official was not authorized to discuss the investigation publicly.
The bizarre scandal surfaced four years ago but has crept back into headlines in recent weeks because Petraeus is among candidates Trump is considering to become secretary of state.
Petraeus resigned as CIA director in November 2012, and later pleaded guilty to one misdemeanor charge of mishandling classified information. He was also fined $100,000 and remains on probation.
The scandal unfolded when the FBI investigated anonymous emails sent to high-ranking military officials and to Kelley's husband, warning them about what was described as Kelley's inappropriate behavior toward the men. The FBI concluded that the emails were from Broadwell, Petraeus' biographer, and as they investigated, they learned of the affair and learned that Petraeus had shared classified materials with Broadwell.
One of the officials who received an anonymous email was Mattis, who Trump announced last week would become his nominee for secretary of defense.
Mattis had been interviewed by the FBI about the email and his statement was memorialized in FBI reports. He told investigators he could not understand why anyone would send him a warning because he always had above-board interactions with Kelley, who he described to the FBI as holding an honorary ambassador title. Mattis had met Kelley when he served as a top officer at U.S. Central Command headquarters in Tampa.
Mattis did not immediately respond to a message left with Trump's transition team.
Emails between Mattis and Kelley were disclosed last year, released under the U.S. Freedom of Information Act. In some emails, Mattis referred to Kelley as "Young Jill." Kelley has said she never behaved inappropriately with Petraeus or any of the military officials she was emailing.
Separately, agents from the Naval Criminal Investigative Service Office of Special Projects had interviewed Mattis about counterintelligence aspects of the case, a U.S. official told the AP. It was considered by the agents to be an especially sensitive assignment because of the allegations against Petraeus about mishandling classified information. The official spoke on condition of anonymity because the official was not authorized to discuss details of the investigation publicly.
Broadwell was not accused of a crime. She told "CBS This Morning" this week that "it was a bit of a shocker that Petraeus was being considered for a Cabinet position," but said both she and Petraeus should be allowed to move on with their lives.
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