Wanis al-Sharef, an interior ministry official in Bengazi, said the two were shot at the consulate during an attack by armed men who stormed the building. He provided no further details.
The angry protest at the consulate Tuesday was sparked by outrage over a film produced by an extreme anti-Muslim Egyptian Christian campaigner in the United States attacking Islam's prophet Muhammed.
Witnesses said the armed men set fire to the consulate and fired shots into the air, burning much of the build.
Update: September 12, 2012
WASHINGTON, Sept 12 (Reuters) - The attack that killed the U.S. ambassador and three other American diplomats in Benghazi, Libya, may have been planned and organized in advance, U.S. government officials said on Wednesday.
The officials said that there were indications that members of a militant faction calling itself Ansar al Sharia - which translates as Supporters of Islamic Law - may have been involved in organizing the attack on the U.S. Consulate in Libya's second-largest city.
They also said some reporting from the region suggested that members of Al-Qaeda's north Africa-based affiliate, known as Al Qaeda in the Islamic Maghreb, may have been involved.
"It bears the hallmarks of an organized attack" and appeared to be preplanned, one U.S. official said.
The officials asked for anonymity when discussing sensitive information. More specific details about the possible role of militant groups or cells in the attack were not immediately available.
One U.S. official noted that, in the wake of the collapse of the government of the late Libyan leader Muammar Gaddafi last year, Libyan government arsenals were looted, making small arms and more sophisticated weapons available both to potential militants and black marketeers.
Some U.S. officials cautioned against assuming that the Benghazi attack, or a similarly-timed violent protest at the U.S. Embassy in Cairo, were deliberately organized to coincide with the anniversary of the Sept. 11, 2001, attacks carried out by al Qaeda in Washington and New York.
U.S. and European officials said that in contrast to the Benghazi attack, which some investigators say may have been calculated and organized, the attack on the U.S. Embassy in Cairo appeared more likely to have been a spontaneous eruption by a mob.
Ambassador Christopher Stevens, Foreign Service Officer Sean Smith and two other Americans who have not yet been identified were killed when gunmen stormed the consulate and another U.S. safe house in Benghazi on Tuesday.
A London think-tank run by a former Libyan militant leader suggested on Tuesday that not only was the Benghazi attack "well planned," but that it may have been retaliation for an American drone attack which killed a Libyan leader of al-Qaeda's core command group earlier this year.
The Quilliam Foundation said that 24 hours before the Benghazi incident, al Qaeda leader, Ayman al-Zawahiri, distributed a video to militant websites in which he confirmed the death of his second in command, known as Abu Yahya al-Libi, and urged Libyans to avenge his killing.
Quilliam, whose president, Noman Benotman, once was a leader of an anti-Gaddafi militant faction known as the Libyan Islamic Fighting Group, said that according to its sources, up to 20 militants had prepared for a military assault.
Quilliam said the assault on the Benghazi Consulate took place in two waves. After the first wave, U.S. officials arranged an evacuation of the Consulate by Libyan security forces. As the evacuation was taking place, a second wave of attacks was launched against U.S. officials who had already been moved to a supposedly secure location, Quilliam said.
The Eurasia Group, a strategic consulting firm, said that it also believed that "the attack on the consulate was an orchestrated response by an organized Salafist (ultra-orthodox Muslim) group."
WASHINGTON -- The battle over the U.S. consulate in Benghazi, Libya, where four American diplomats lost their lives Tuesday night, lasted for approximately four hours, a senior administration official said in a press briefing Wednesday afternoon.
Three American staffers -- including Ambassador J. Christopher Stevens, who later died in the assault -- were inside the main building of the compound around 10 p.m. local time, when the facility started taking small-arms fire from outside, the official said.
Within 15 minutes, the attackers had breached the outside wall of the consulate and began targeting that main building, soon setting it on fire. Initial reports had suggested that the attackers used rocket-propelled grenades, something the administration official could not confirm.
The three Americans in the building -- a U.S. regional security officer, Ambassador Stevens, and Sean Smith, a Foreign Service information technology officer who also later died -- "became separated from each other due to heavy dark smoke while trying to evacuate," the official said.
"The RSO [regional security officer] made it outside, and then he and other security personnel returned into the burning building in an attempt to rescue Chris and Sean," the official said. "At that time they found Sean, he was already dead, and they pulled him from the building. They were unable, however, to locate Chris before being driven from the building due to heavy fire and smoke."
U.S. security officers, working together with Libyan guards and a local militia friendly to the Americans, were not able to retake control of the compound until after 2 a.m. local time, the official said. Ambassador Stevens' body was later delivered to American officials at the airport, sometime near dawn, but officials were unable to confirm when exactly he had died and how.
Recent reports have indicated that the attack on the compound in Benghazi may have been planned by a radical Islamic terrorist group, rather than being the result of protests that got out of hand, as many first assumed. The U.S. Embassy in Cairo was also stormed amid protests, driven by a little-known film that depicts the Prophet Muhammad in a negative light and has circulated on the Internet, but no Americans were wounded during that incident.
The official who was briefing reporters Wednesday emphasized repeatedly that the administration's information was still composed of sketchy "first reports" and said that times and details "could very well change as we get a better understanding."