[Initial post, 3:08 p.m.] CIA Director David Petraeus submitted his resignation Friday to President Barack Obama, citing personal reasons, a U.S. government source said. [Updated at 3:41 p.m.] David Petraeus met with President Barack Obama on Thursday, at which time the then CIA director offered his resignation, a senior administration official said. [Updated at 3:38 p.m.] President Obama said, in a statement, that today he accepted Petraeus' resignation as CIA director. [Updated at 7:11 p.m.] The FBI investigated a tip that the woman Petraeus was involved in an extramarital affair with was Paula Broadwell, who co-wrote a biography about him, a U.S. official said. CNN has not been been able to reach Broadwell for comment. A retired U.S. Army general who served as the top U.S. commander in Iraq and Afghanistan, Petraeus was sworn in as the head of the CIA in September 2011. [Updated at 4:52 p.m.] Acting CIA Director Michael Morrell will testify next week before the Senate Intelligence Committee about the fatal attack in Benghazi instead of David Petraeus, according to the office of that committee's chairwoman, Sen. Dianne Feinstein.  Editor's note: Retired Gen. David Petraeus stepped down Friday as head of the Central Intelligence Agency - 14 months after taking the job, days after the presidential election and days before he was to testify before Congress about an attack on a U.S. consulate in Libya that left four Americans dead. [Updated at 3:53 p.m.] The chairman of the House Homeland Security Committee praised outgoing CIA Director David Petraeus, saying, "I regret his resignation and wish him and his family the very best." "Gen. Petraeus is one of America's most outstanding and distinguished military leaders and a true American patriot," said Rep. Peter King, a Republican from New York. McCain, an Arizona Republican and the ranking member of the Senate Armed Services Committee, added, "His inspirational leadership and his genius were directly responsible - after years of failure - for the success of the surge in Iraq." [Updated at 4:25 p.m.] U.S. Sen. John McCain extolled Petraeus as one of "America's greatest military heroes," expressing his gratitude for his "decades of work on behalf of our nation, our military and our security." The following message was released to the CIA workforce this afternoon: 
 
 Message from the Director 
 
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 Yesterday afternoon, I went to the White House and asked the President to be allowed, for personal reasons, to resign from my position as D/CIA. [Updated at 3:13 p.m.] Petraeus issued a statement announcing his resignation, saying, "After being married for over 37 years, I showed extremely poor judgment by engaging in an extramarital affair. "Such behavior is unacceptable, both as a husband and as the leader of an organization such as ours. The president then formally accepted Petraeus' resignation in a phone call Friday afternoon, according to the same official. As I depart Langley, I want you to know that it has been the greatest of privileges to have served with you, the officers of our Nation's Silent Service, a work force that is truly exceptional in every regard. Indeed, you did extraordinary work on a host of critical missions during my time as director, and I am deeply grateful to you for that. 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. Thank you for your extraordinary service to our country, and best wishes for continued success in the important endeavors that lie ahead for our country and our Agency. With admiration and appreciation, 
 
 David H. Petraeus 
 
 Andrea Mitchell is NBC News’ chief foreign affairs correspondent.
– Wow. We knew President Obama would be replacing plenty of key people, but not like this: CIA chief David Petraeus is resigning over an extramarital affair, reports NBC News. Details are still scarce, but Petraeus has submitted his letter of resignation, which begins: "Yesterday afternoon, I went to the White House and asked the President to be allowed, for personal reasons, to resign from my position as D/CIA. After being married for over 37 years, I showed extremely poor judgment by engaging in an extramarital affair. Such behavior is unacceptable, both as a husband and as the leader of an organization such as ours. This afternoon, the President graciously accepted my resignation." (Full text here.) Petraeus took over the CIA in 2011 after leading the wars in Iraq and Afghanistan, and Obama praised him today for his "extraordinary service," reports CNN. The president's statement didn't mention the scandal except to say that his “thoughts and prayers are with Dave and Holly Petraeus" at this "difficult time." Deputy CIA director Mike Morrell is expected to step in on an interim basis and may get the job permanently, says NBC. (Update: Slate is reporting that the "other woman" is Petraeus' biographer. Click for that.)