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. 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. 
 
 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 ||||| 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 7:59 p.m.] Speaking on CNN's "Erin Burnett OutFront," Rep. Peter King (R-New York) called Petraeus' resignation "a real loss for the country, a real loss for the CIA." 
 
 "We're going to lose the best man for the job, but again America is adaptable," said the chairman of the House Homeland Security Committee. "Put it this way, anytime you lose a David Petraeus, the country is not as safe as it could be." 
 
 [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. 
 
 Broadwell spent a year with Petraeus in Afghanistan, interviewing him for the book "All In: The Education of General David Petraeus." 
 
 CNN has not been been able to reach Broadwell for comment. It is not clear if Broadwell is the woman with whom Petraeus had admitting having an affair, leading to his resignation Friday as the head of the CIA. 
 
 [Updated at 5:43 p.m.] After getting a tip that Petraeus was involved in an extramarital affair, the FBI launched an investigation to see if this relationship posed a "potential security risk," a U.S. official said. The official added there is no suggestion the FBI was probing Petraeus for any criminal wrongdoing, only because they feared he might be "in a vulnerable spot." 
 
 [Updated at 5:40 p.m.] The woman who David Petraeus had an affair with was not a member of the armed forces or the CIA, sources close to Petraeus told HLN's Kyra Phillips. The retired general is extremely disappointed in himself and devastated that he's hurt his family, the sources say. 
 
 [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. 
 
 [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." 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 3:59 p.m.] Sen. Dianne Feinstein, the head of the Senate Intelligence Committee, said, "I wish President Obama had not accepted this resignation, but I understand and respect the decision." 
 
 The California Democrat praised Petraeus for giving the CIA "leadership, stature, prestige and credibility both at home and abroad," calling him reliably in "command of intelligence issues" and "especially cooperative with Congress." 
 
 [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. 
 
 
 
 [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. The president then formally accepted Petraeus' resignation in a phone call Friday afternoon, according to the same official. 
 
 [Updated at 3:38 p.m.] President Obama said, in a statement, that today he accepted Petraeus' resignation as CIA director. 
 
 The president added he is "completely confident that the CIA will continue to thrive and carry out its essential mission," now under the leadership of Acting Director Michael Morrell. 
 
 Obama lauded Petraeus for his "extraordinary service to the United States for decades," calling him "one of the outstanding general officers of his generation" and praising his work as CIA director. 
 
 The president concluded by saying, "Going forward, my thoughts and prayers are with Dave and Holly Petraeus, who has done so much to help military families through her own work. I wish them the very best in this difficult time." Holly Petraeus led the Consumer Financial Protection Bureau’s Office for Servicemembers Affairs. 
 
 [Updated at 3:17 p.m.] Shortly before Petraeus' resignation was announced, White House press secretary Jay Carney told reporters that "the president thinks Gen. Petraeus has done an excellent job." 
 
 When asked about the general's job status, Carney reiterated that President Obama approves of the job done by the CIA director while adding, "I don't have personnel announcements to make from here today." 
 
 [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. This afternoon, the president graciously accepted my resignation." 
 
 [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. 
 
 According to the source, Petraeus admitted to having an extramarital affair when he asked to resign. 
 
 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. 
 
 Director of National Intelligence James Clapper issued a statement Friday confirming that Petraeus had turned in his resignation, saying his "decision to step down represents the loss of one of our nation's most respected public servants." ||||| These crawls are part of an effort to archive pages as they are created and archive the pages that they refer to. That way, as the pages that are referenced are changed or taken from the web, a link to the version that was live when the page was written will be preserved.Then the Internet Archive hopes that references to these archived pages will be put in place of a link that would be otherwise be broken, or a companion link to allow people to see what was originally intended by a page's authors.The goal is to fix all broken links on the web . Crawls of supported "No More 404" sites. ||||| NBC's Brian Williams and NBC's Andrea Mitchell report on the resignation of well-regarded former General David Petraeus from the CIA after he admitted an affair. 
 
 WASHINGTON -- CIA Director David Petraeus resigned Friday, citing an extramarital affair and "extremely poor judgment." 
 
 As first reported by NBC News, Petraeus disclosed the affair in a letter released to the CIA work force on Friday afternoon, writing: "Such behavior is unacceptable, both as a husband and as the leader of an organization such as ours." 
 
 Petraeus told President Barack Obama of his affair and offered his resignation during a meeting Thursday, a senior official told NBC News. 
 
 In a statement, Obama said he accepted Petraeus’s resignation on Friday. 
 
 "By any measure, through his lifetime of service, David Petraeus has made our country safer and stronger," Obama said of the four-star general, who led American forces in Iraq and Afghanistan. 
 
 Petraeus' biographer, Paula Broadwell, is under FBI investigation for improperly trying to access his email and possibly gaining access to classified information, law enforcement officials told NBC News on Friday. She is the author of Petraeus' biography, "All In." Broadwell had extensive access to Petraeus in Afghanistan and has given numerous television interviews speaking about him. 
 
 Law enforcement and multiple U.S. officials told NBC News that emails between Petraeus and Broadwell were indicative of an extra-marital affair. 
 
 Broadwell could not be reached by NBC News for comment. 
 
 David Petraeus a battlefield 'hero' and savvy Washington insider 
 
 Petraeus himself is not under investigation. 
 
 A U.S. military official and long-time aide to Petraeus told NBC News the director resigned "because he screwed up." 
 
 "In his mind, in his views, with his code of ethics and morals, he did a very dishonorable thing," the official said. "This had nothing to do with Benghazi, nothing to do with his relationship with the White House." 
 
 Petraeus was appointed CIA director in April 2011, replacing Leon Panetta, who moved to the Pentagon to become defense secretary. 
 
 Petraeus served as commander of the war in Afghanistan in 2010-2011. Before that, he served as commander of the U.S. Central Command and as the commanding general of U.S. forces in Iraq. Because of those roles, he was seen as bringing a “customer’s eye” to the intelligence job. 
 
 Sen. Dianne Feinstein, D-Calif., chair of the Senate Intelligence Committee, told NBC News that Petraeus’s personal mistake should not have led to his departure. 
 
 "I would have stood up for him," Feinstein said in response to his indiscretion. "I wanted him to continue. He was good, he loved the work, and he had a command of intelligence issues second to none." 
 
 Mandel Ngan / AFP - Getty Images file General David Petraeus, center, takes the oath of office as the next director of the CIA from Vice President Joe Biden, right, as Petraeus's wife, Holly, watches on Sept. 6, 2011 during a ceremony at the Roosevelt Room of the White House in Washington, D.C. 
 
 Feinstein said she respects Obama’s decision to accept the Petraeus resignation, but wishes he hadn't. 
 
 She also said Petraeus will not need to testify at hearings she is chairing next week into the attack on the U.S. consulate in Benghazi, Libya. Ambassador Christopher Stevens and three other Americans were killed in the attack. 
 
 Rep. Peter King, R-NY, chairman of the House Committee on Homeland Security, said he regrets Petraeus's resignation. "General Petraeus is one of America's most outstanding and distinguished military leaders and a true American patriot," King said in a statement. 
 
 Sen. John McCain, R-Ariz., said it was Petraus's "genius" that was responsible "for the success of the surge in Iraq." 
 
 "General David Petraeus will stand in the ranks of America's greatest military heroes," McCain said in a statement. 
 
 Multiple sources tell NBC News that Mike Morrell, the deputy CIA director and a longtime CIA officer, would likely be offered the job as acting director, with the understanding that he may be elevated to the job permanently. 
 
 That's how George Tenet got the job, first as deputy director in July 1995, then acting director following the resignation of John Deutch in December 1996 and finally as director in July 1997, staying on in the Bush administration. 
 
 Morrell is a longtime CIA analyst and was an eyewitness to two of the most momentous events in recent U.S. history. He was traveling with President George W. Bush on Sept. 11, 2001, as the president's briefer, and was in the Situation Room on May 1, 2011, as deputy CIA Director, when Navy SEALs killed Osama bin Laden. 
 
 Morell began his agency career as an analyst tracking international energy issues and subsequently worked for 14 years as an analyst and manager on East Asia. In 1999, he was appointed director of the Office of Asian Pacific and Latin American Analysis. He also has served as a presidential briefer, as chief of the staff that produces the president's daily briefing, and as an executive assistant to CIA Director George J. Tenet. 
 
 From 2003 until 2006, he served overseas. Upon his return, he was briefly deputy director for intelligence at the National Counterterrorism Center before being asked to become associate deputy director at the CIA. 
 
 NBC's Andrea Mitchell reports on the resignation of CIA Director David Petraeus after citing an extra-marital affair and apologizing for poor judgment. 
 
 Here is the full text of Petraeus' letter: 
 
 HEADQUARTERS Central Intelligence Agency 9 November 2012 
 
 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. 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. Robert Windrem is NBC News’ senior investigative producer. NBC News Chief White House Correspondent Chuck Todd contributed to this report. 
 
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– 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.)