An FBI investigation into a potential case of "cyber-harassment" involving Gen. David Petraeus' biographer, Paula Broadwell, began several months ago and concluded four days before the presidential election, a senior U.S. law enforcement official told NBC News. According to the official, this was the second time Broadwell was questioned in the probe, during which she acknowledged having had an affair with the retired general. Petraeus was questioned a few days earlier and also acknowledged the affair, the official told NBC News. Those interviews, which took place in the last week of October, allowed the FBI to conclude there was no basis for criminal charges, which accounted for why the Director of National Intelligence James Clapper wasn't informed about the probe until election day. "This had nothing to do with the election," the official told NBC News. The official added that the FBI and Justice Department's decisions on the case were not governed by the political calendar, nor were they influenced by a phone call from House Majority Leader Eric Cantor's office to the FBI on Oct. 31 asserting that it had heard from a FBI whistleblower. In fact, the investigation began several months ago when a woman reported to the FBI she was receiving anonymous and harassing emails, the senior official told NBC News. Multiple government officials identified the woman to NBC News as close Petraeus family friend Jill Kelley, who lives in Tampa, Florida.