Gen. David Petraeus has surprisingly and abruptly resigned as director of the CIA.
The decorated former chief of U.S. Central Command cited an extramarital affair, with reports later identifying biographer Paula Broadwell as his mistress.
"After being married for over 37 years, I showed extremely poor judgment by engaging in an extramarital affair," Petraeus' resignation letter said.
"Such behavior is unacceptable, both as a husband and as the leader of an organization such as ours."
"Teddy Roosevelt once observed that life's greatest gift is the opportunity to work hard at work worth doing."
"I will always treasure my opportunity to have done that with you and I will always regret the circumstances that brought that work with you to an end."
The retired four-star Army general had a distinguished 37-year career in the military before joining the CIA, commanding forces in Iraq and Afghanistan.
Petraeus, 60, has been widely praised by both sides of the political aisle.
He took the helm of the CIA in September 2011; his sudden resignation came as a surprise, just days after President Barack Obama won reelection.
President Obama said in a statement:
"By any measure, he was one of the outstanding officers of his generation, helping our military adapt to new challenges, and leading our men and women in uniform through a remarkable period of service in Iraq and Afghanistan, where he helped our nation put those wars on a path to a responsible end."
"As director of the Central Intelligence Agency, he has continued to serve with characteristic intellectual rigor, dedication and patriotism."
Obama accepted Petraeus' resignation Friday.
Michael Morell, until today the Deputy Director of the Central Intelligence Agency, has been named Acting Director; Obama's plans for a permanent replacement aren't known.
Petraeus and his wife, Holly, have been married since 1974 live in Virginia. They have two grown children.