Lawmakers spent hours Thursday interviewing top intelligence and national security officials in trying to determine what intelligence agencies knew before, during and after the attack. They viewed security video from the consulate and surveillance footage by an unarmed CIA Predator drone that showed events in real time.
Petraeus started with the House committee, which met in a secure room several floors below the main area of the Capitol Visitors Center where tourists gather when they are visiting Congress.
"Director Petraeus went to Tripoli and interviewed many of the people involved," said the head of the Senate committee, California Democrat Dianne Feinstein.
Added Rep. Adam Schiff, D-Calif.: ""I'd like to get his sense of why it took as long as it did to get more accurate assessments of what took place in Benghazi."
As for Petraeus testifying after his resignation amid a sex scandal, Schiff said, "He's a tough individual and I am sure he will handle it to the best of his ability."
Petraeus has acknowledged an affair with a woman later identified as his biographer, Paula Broadwell. The FBI began investigating the matter last summer but didn't notify the White House or Congress until after the election.
In the course of investigating the Petraeus affair, the FBI uncovered suggestive emails between Afghanistan war chief Gen. John Allen and Florida socialite Jill Kelley, both of them married. President Barack Obama has put a promotion nomination for Allen on hold.
National security officials trudged to Capitol Hill on Thursday to grapple with fallout from the sex scandal as Defense Secretary Leon Panetta asked service chiefs to review ethics training for military officers.
Lawmakers went forward with a hearing on the nomination of Gen. Joseph Dunford to replace Allen in Afghanistan. But with Allen's own future uncertain, they put off consideration of his promotion to U.S. European Command chief and NATO supreme allied commander. Allen had initially been scheduled to testify.
Administration officials met privately with lawmakers for a third straight day to explain how the Petraeus investigation was handled and explore its national security implications. Among those appearing before the House committee were Director of National Intelligence James Clapper and acting CIA Director Michael Morell.
Rep. Dutch Ruppersberger of Maryland, the committee's top Democrat, said after the hearing that he was satisfied that the FBI had behaved properly in not notifying the White House or lawmakers about the inquiry sooner, in keeping with post-Watergate rules set up to prevent interference in criminal investigations.
The CIA on Thursday opened an exploratory investigation into Petraeus' conduct. The inquiry "doesn't presuppose any particular outcome," said CIA spokesman Preston Golson. At the same time, Army officials say that, at this point, there is no appetite for recalling Petraeus to active duty to pursue any adultery charges against him.
Petraeus, in his first media interview since he resigned, told CNN that he had never given classified information to Broadwell. She has said she didn't receive such material from Petraeus.
But the FBI found a substantial number of classified documents on Broadwell's computer and in her home, according to a law enforcement official, and is investigating how she got them. That official spoke only on condition of anonymity because the official was not authorized to speak publicly about the case. The Army has now suspended her security clearance.