The timeline below details the ongoing investigation into the September 11, 2012 attack upon the American diplomatic mission at Benghazi, in Libya. The attack and the investigation are the subject of much controversy in the American political sphere.

Timeline

September 2012 September 12 The New York Times reported: "American and European officials said that while many details about the attack remained unclear, the assailants seemed organized, well trained and heavily armed, and they appeared to have at least some level of advance planning." The article also noted that a senior Obama administration official told reporters that "it was clearly a complex attack," but provided no details.

CBS News reported that Wanis al-Sharef (also spelled al-Sharif), a Libyan Interior Ministry official in Benghazi, said that an angry mob had gathered outside the consulate to protest a U.S.-made film that schedule ridiculed the Islamic prophet Muhammad. According to al-Sharef, the mob stormed the consulate after the U.S. troops who responded fired rounds into the air to try and disperse the crowd.

CBS News later reported that U.S. officials said the attack was not an out-of-control demonstration as first suspected, but a well-executed assault. From the wording of the report it is unclear whether the protesters were a group distinct from the attackers or were the attackers themselves.

The Guardian published a video interview of a local Libyan on the consulate compound right after the attack, who presumed and empathized that the attack was in response to the anti-Islamic film.

The Washington Post reported that U.S. officials and Middle East analysts said that the attack "may have been planned by extremists and inspired by al-Qaeda."

In a press release, the Qulliam Foundation, a counter-extremism think tank based in London, stated that the "military assault" was not related to the film but was to "avenge the death of Abu Yahya al-Libi, al-Qaeda's second in command killed a few months ago."

BBC reported that Libya's deputy ambassador to London, Ahmad Jibril, named Ansar al-Sharia, also known as Al-Qaeda in the Arabian Peninsula, as the perpetrators. They also said a Libyan reporter told them that the attack was executed by as many as 80 militiamen "armed with assault rifles, rocket-propelled grenades, mortars and 14.5 mm anti-aircraft machine guns."

Deputy Interior Minister Wanis al-Sharif of the Libyan government told a news conference in Benghazi that it was likely that the perpetrators had been Gaddafi loyalists, suggesting the attack could have been intended as a revenge for the extradition of Abdullah al-Senoussi (Gaddafi's former intelligence chief) from Mauritania the previous month. September 13The FBI opened an investigation into the deaths; a team was sent to investigate, with another team for security. The FBI officials were set to arrive by September 21 in Benghazi to work with Libyan officials.

In a briefing to congressional staffers, State Department Under Secretary Patrick Kennedy said that the attack appeared planned because it was so extensive and because of the "proliferation" of small and medium weapons.

CNN reported that the attackers were part of an Al Qaeda spinoff group. They spoke with Sen. Dianne Feinstein (D-Calif.), who said the killings were possibly linked to the terrorist group blamed for the 9/11 hijackings. According to Sen. Feinstein, "The weapons were somewhat sophisticated, and they blew a big hole in the building and started a big fire."September 14The Senate Armed Services Committee was briefed by Secretary of Defense Leon Panetta about the response to the situation in Libya. Afterwards, Senate Armed Services Chairman Carl Levin (D-MI) was quoted as saying, "I think it was a planned, premeditated attack." He added that he did not know the group responsible for the attack.September 15SITE Intelligence Group released a report that said al-Qaeda claimed that the attack was in revenge for the killing of the network's number two Sheikh Abu Yahya al-Libi.Al-Qaida says US consulate attack 'revenge' | thetelegraph.com.au

Talking points prepared by the CIA, stated "The currently available information suggests that the demonstrations in Benghazi were spontaneously inspired by the protests at the U.S. Embassy in Cairo and evolved into a direct assault against the U.S. Consulate and subsequently its annex. There are indications that extremists participated in the violent demonstrations."September 16In an interview with NPR in Benghazi, President Mohammed el-Megarif said that foreigners infiltrated Libya over the past few months, planned the attack, and used Libyans to carry it out. According to el-Megarif: "The idea that this criminal and cowardly act was a spontaneous protest that just spun out of control is completely unfounded and preposterous. We firmly believe that this was a precalculated, preplanned attack that was carried out specifically to attack the U.S. Consulate." He said the attackers used the protesters outside the consulate as a cover, and there is evidence showing that elements of Ansar al-Sharia, an extremist group in eastern Benghazi, were used by foreign citizens with ties to al-Qaida to attack the consulate.

U.S. Ambassador to the United Nations Susan Rice appeared on several Sunday morning talk shows and stated, "Putting together the best information that we have available to us today our current assessment is that what happened in Benghazi was in fact initially a spontaneous reaction to what had just transpired hours before in Cairo, almost a copycat of-- of the demonstrations against our facility in Cairo, which were prompted, of course, by the video. What we think then transpired in Benghazi is that opportunistic extremist elements came to the consulate as this was unfolding. They came with heavy weapons which unfortunately are readily available in post revolutionary Libya. And it escalated into a much more violent episode."

Senator John McCain (R-AZ), the top Republican on the Senate Armed Services Committee, voiced suspicion that the attack was planned in advance and not prompted by the furor over the film. He noted that "[m]ost people don't bring rocket-propelled grenades and heavy weapons to demonstrations. That was an act of terror." September 17Fox News reported that an "intelligence source on the ground in Libya" said "there was no demonstration outside the U.S. Consulate in Benghazi" before the attack. The source was quoted as saying, "There was no protest and the attacks were not spontaneous." The source also said that the attack "was planned and had nothing to do with the movie." The source said the assault came with no warning at about 9:35 p.m. local time and included fire from more than two locations. The information for the time and for multiple directions of the attack corroborates an eyewitness report.

Representative Mike Rogers (R) Michigan, the chairman of the House Intelligence Committee, said in an interview with Real Clear Politics that there were reports that the Consulate sustained "indirect fire, artillery type fire from mortars. They had direct unit action. It was coordinated in a way that was very unusual. They repulsed a quick reaction force that came to the facility...."September 19The director of the National Counterterrorism Center, Matthew Olson, appeared before the Senate Homeland Security and Governmental Affairs Committee. During the hearing Olsen said that the Americans killed in Libya died "in the course of a terrorist attack." But he said that "the facts that we have now indicate that this was an opportunistic attack," one in which heavily armed militants took advantage of an ongoing demonstration at the Consulate.

Sen. Susan Collins (R-Maine) disagreed with Olsen's statement that the attack did not appear pre-planned. She said, "Based on the briefings I have had, I've come to the opposite conclusion. I just don't think that people come to protests equipped with RPGs [rocket-propelled grenades] and other heavy weapons. And the reports of complicity—and they are many—with Libyan guards who were assigned to guard the consulate also suggest to me that this was premeditated." Olsen told committee members that the U.S. is "looking at indications" that some attackers had connections to al-Qaeda or its North African affiliate, al-Qaeda in the Islamic Maghreb.

Fox News reported intelligence sources that the attack was tied to Al Qaeda via the involvement of Abu Sufian bin Qumu, a former Guantanamo Bay detainee. However, a US national security official tells Mother Jones that "that report is wrong, there's no intelligence suggesting that he was leading the attack on the consulate that evening." September 20Reuters reported that U.S. authorities are investigating the prospect of collusion between the militants who launched the attack on the consulate and locally hired Libyan personnel guarding the facility. This corroborates earlier statements by U.S. government officials who stated there were multiple accounts of collusion between the attackers and the Libyan security guards.

Secretary Clinton announced the formation of a panel to investigate the attack, which is separate from the FBI investigation.

White House Press Secretary Jay Carney for the first time called the event "a terrorist attack." In the same report CNN noted conflicting reports that U.S. Ambassador to Libya Chris Stevens "believed he was on an al Qaeda hit list."September 21U.S. officials said that the heavily armed extremists who laid siege to the consulate used "military-style tactics" in what appeared to be a "sophisticated operation". Intelligence reports indicated that 50 or more people, many of them masked, took part in the attack and used gun trucks and precise mortar fire. Intelligence reports also indicated that the attackers set up a perimeter to control access in and out of the compound. September 23A report in The New York Times has stated that there were two facilities used by the Americans in Benghazi, one for the American mission and an annex a half-mile away and that: Neither was heavily guarded, and the annex was never intended to be a "safe house," as initial accounts suggested. Two of the mission's guards — Tyrone S. Woods and Glen A. Doherty, former members of the Navy SEALs — were killed just outside the villa's front gate.September 25U.S. Senators John McCain (R-AZ), Lindsey Graham (R-SC), Kelly Ayotte (R-NH) and Ron Johnson (R-WI) sent a letter to U.N. Ambassador Susan Rice seeking clarification on statements she made on the five Sunday talk shows on September 16 that the September 11 attack in Benghazi was the result of a "spontaneous reaction." The senators wrote that the evidence clearly showed the attack was planned and coordinated. Ms. Rice wrote in her reply letter, "I relied solely and squarely on the information the intelligence community provided to me ... This information represented the intelligence community's best, current assessment as of the date of my television appearances." The four senators replied in a statement: "Elements of the intelligence community apparently told the administration within hours of the attack that militants connected with al Qaeda were involved, yet Ambassador Rice claims her comments five days later reflected the 'best' and 'current' assessment of the intelligence community. Either the Obama administration is misleading Congress and the American people, or it is blaming the entire failure on the intelligence community."September 26The Daily Beast reported that three separate U.S. intelligence officials knew within 24 hours of the attack that it was "planned and the work of al Qaeda affiliates operating in Eastern Libya."