General John Allen, the man who succeeded David Petraeus as the top U.S. commander in Afghanistan, reportedly sent hundreds of "potentially inappropriate" emails to one of the women involved in the scandal that led to Petraeus' resignation from the CIA. The Department of Defense has announced that the FBI investigation into the relationship between Petraeus and his biographer, Paula Broadwell, has now been expanded to include Allen, who is currently the commander of the International Security Assistance Force (ISAF) in Afghanistan. (That's him on the left in the photo above, with Petraeus and the Secretary of Defense.)

The FBI informed the Pentagon on Sunday that Allen sent between "20,000 and 30,000 pages" of emails to Jill Kelley, the woman who had her own close relationship with Petraeus and who first alerted the FBI to the relationship between Broadwell and Petraeus. There is no indication of what might be in the emails (though the thousands of pages figure likely indicates numerous data-heavy pictures) or the nature of Kelley and Allen's relationship, but Allen has denied any wrongdoing.

The FBI also searched Broadwell's home last night, leaving with several cardboard boxes of evidence, but did not say what they were after.

So let's see if we can connect the dots one more time: Petraeus and Broadwell have an affair. That affair ends. Broadwell believes that Petraeus and Kelley are also having affair. Broadwell begins emailing Kelley about Petraeus and Allen, who used to work for Petraeus and already had some sort of relationship with Kelley ... who also started getting weird emails from the FBI agent who started the investigation on her behalf. Oh, and all of them are married to other people this entire time. Got that?

Now Allen's case has been referred to the Inspector General at the Department of Defense who will do their own investigation. Complicating matters even further is the fact that Allen was set to be nominated to be the Supreme Allied Commander in Europe, one of the highest ranking military commands in the U.S. Army. That nomination (which must be confirmed by the Senate) is now on hold, but Secretary of Defense Leon Panetta has also asked the President to expedite the nomination of Allen's successor at ISAF. Allen will remain in his post for now, but if things go badly for him he could be replaced more quickly that way.