The U.S. Defense Department is investigating General John Allen, the top U.S. commander in Afghanistan, for alleged "inappropriate communications" with a woman involved in the scandal that led to the resignation of Central Intelligence Agency chief David Petraeus.
A senior defense official said Tuesday that the Pentagon is reviewing more than 20,000 pages of emails and other communications between General Allen and Jill Kelley. The official did not specify the nature of the documents.
Kelley is a friend of Petraeus, and it was her complaint to the Federal Bureau of Investigation about threatening emails from the woman with whom Petraeus had an affair that ultimately led to his resignation last Friday.
Pentagon spokesman George Little said the FBI brought the matter involving General Allen to the Defense Department Sunday, and that Defense Secretary Leon Panetta has directed the department's inspector-general to investigate.
General Allen has denied any wrongdoing, and will retain his command position in Afghanistan while the probe continues.