PEOPLE goes inside the CIA scandal where a Tampa socialite’s concern about anonymous e-mails exposed the affair between CIA director Gen. David Petraeus and Paula Broadwell – and then ensnared her family and another four-star general. Jill Kelley – an unpaid community liaison at MacDill Air Force Base, who placed herself at the nexus of Tampa’s military-civilian circles since moving there with her husband, Scott, and twin, Natalie Khawam, a decade ago – inadvertently exposed a scandal that involves both Petraeus, who stepped down as head of the CIA after admitting an affair with his biographer Broadwell, and Gen. John Allen, whose promotion to head NATO forces in Europe is in limbo while what government officials describe as suggestive e-mails he wrote to Kelley are reviewed by the Defense Department.

For military lifers like Petraeus and Allen stationed at Central Command in Tampa, the relative glitz Kelley and her sister brought proved enchanting. “Here’s the thing about commanders: They can get isolated. It’s nice to have civilian friends who support you and the mission,” says an active duty Army community-outreach official. “Mostly it’s a nice thing. This one backfired.” Adds a former MacDill Army colonel, “A few of us on base called them Jill and Natalie Kardashian. They were like junior high girls, name-dropping.” It merely annoyed locals, but Kelley’s friendships with the generals really didn’t sit right with Broadwell, who until late this spring had been careful about not exposing her personal interest in Petraeus. Then, says a source close to Kelley, anonymous e-mails started to appear, first written under the name KelleyPatrol and sent to General Allen, warning him about Kelley as a person who could harm his reputation.

Then the Kelleys began receiving anonymous e-mails (under another name), which this source characterizes as saying, “Think twice – who are you to be hanging out with generals and ambassadors and officials?” Kelley went to local FBI agent Frederick Humphries II, who, says this source, felt “it worthy of being looked into.” It was that call that ultimately led to Broadwell being pinned as the author of the e-mails and – four months later – to Petraeus coming clean about the affair. “Fred has great instincts,” says a former FBI coworker. “He knew something was amiss, and he was right.” Unfortunately for Humphries, who is generally lauded as a hero for his work foiling a 1999 al-Qaeda plot to bomb the Los Angeles airport, personal photos he sent to Kelley and other friends have landed him in the spotlight too. Despite the amusing moments, the scandal raises serious questions of national security and military conduct. “A select committee would look at everything,” Virginia’s GOP Rep. Frank Wolf tells PEOPLE. “Maybe there’s no problem here, but the American people need to know.”

About the affair and its aftermath, Broadwell is “devastated,” her brother Stephen Kranz tells PEOPLE. “It’s clear she is filled with guilt and shame for what she’s done, and she’s incredibly sorry for the pain she’s caused her husband, her family, Petraeus’s family.” As for how Petraeus’s wife, Holly, feels after 38 years of marriage and 23 military relocations: “Furious would be an understatement,” said an insider.

With no one in the whole affair blameless of bad judgment, someone who has worked with Broadwell – Michael O’Hanlon, director of research at the Brookings Institution – says, “She lost some of her emotional balance with [Kelley], and there were missteps she made along the way. But Paula is a dedicated parent, did some serious research [for her book] and is dedicated to the Wounded Warrior cause. She made a huge mistake. But she made only half of this decision. Petraeus made the other half.”

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