TAMPA, Fla. (AP) — A Florida socialite at the center of a sex scandal surrounding former CIA Director David Petraeus is now part of an investigation into the top U.S. commander in Afghanistan over thousands of alleged "inappropriate communications" between the two.

Jill Kelley is a close friend of Petraeus' and served as a sort of social ambassador for U.S. Central Command in Tampa, hosting parties for the general when he was commander there from 2008-10. The 37-year-old woman's complaint about an anonymous, threatening email triggered an FBI investigation that uncovered Petraeus' affair and led to his downfall.

Now investigators are poring over email between Kelley and Gen. John Allen, who succeeded Petraeus as the top American commander in Afghanistan in July 2011. Allen has denied wrongdoing.