Esam Omran Al-Fetori / Reuters
Demonstrators hold a message during a rally to condemn the killers of the U.S. Ambassador to Libya and the attack on the U.S. consulate, in Benghazi on Wednesday.
Libyan authorities have made four arrests in the investigation into the attack on the U.S. Consulate in Benghazi in which the U.S. ambassador and three embassy staff were killed, the deputy interior minister said on Thursday.
"Four men are in custody and we are interrogating them because they are suspected of helping instigate the events at the U.S. Consulate," Wanis Sharif told Reuters.
He gave no more details.
The United States and Libya has agreed to cooperate to find out who was responsible for the deadly attack on the U.S. Consulate in Benghazi in which the ambassador to the North African state and three other Americans died.
President Barack Obama and Libyan President Mohamed Magarief spoke on Wednesday evening and decided "to work closely over the course of this investigation," the White House said in a statement.
TODAY's Matt Lauer speaks with security analyst Michael Leiter about the likelihood that the attack on a U.S. consulate in Libya was a pre-meditated act by a group of al-Qaida sympathizers rather than a spontaneous uprising over an anti-Muslim Internet video.
Magarief "expressed appreciation for the cooperation we have received from the Libyan government and people in responding to this outrageous attack, and said that the Libyan government must continue to work with us to assure the security of our personnel going forward," the White House statement said.
"The President made it clear that we must work together to do whatever is necessary to identify the perpetrators of this attack and bring them to justice," it added.
In Yemen, protesters breach the of the U.S. Embassy compound in the capital, Sanaa, as a wave of anti-American demonstrations sweeps across several Middle East nations. NBC's Richard Engel reports from Cairo.
U.S. and Libyan officials, independent analysts and postings on Islamist websites from known militant activists suggested that the attack — which officials had previously suggested was retaliation for release of a movie critical of the Muslim Prophet Muhammad — may have been a pre-planned, orchestrated assault.
Ambassador Christopher Stevens, Sean Smith — a Foreign Service information management officer — and two other Americans, who have not yet been formally identified, were killed.
A deadly attack on the U.S. consulate in Libya was staged by militants who set the building on fire. NBC's Richard Engel reports.
Destroyers sent to Libya coast
A U.S. official told Reuters that the U.S. military was moving two destroyers toward the Libyan coast, giving the Obama administration flexibility for any future action against Libyan targets.
Timeline: Political fallout from the attack on diplomats in Libya
The military is also dispatching a Marine Corps anti-terrorist security team to boost security in Libya, and Washington has ordered the evacuation of all U.S. personnel from Benghazi to Tripoli.
An unnamed senior U.S. official told the AFP news agency that U.S. officials suspected the attack on the consulate was a well-planned assault by militants rather than a rampaging mob.
NBC's Richard Engel and Ambassador Marc Ginsberg discuss the latest in Libya and Egypt as protest continue outside the U.S. Embassy in Cairo.
"That's the working hypothesis at the moment," said the official, who spoke on condition of anonymity.
"This was a complex attack," he added. "They seemed to have used this (protest) as an opportunity."
Among the assailants, Libyans identified units of a heavily armed local Islamist group, Ansar al-Sharia, which sympathizes with al-Qaida and derides Libya's U.S.-backed bid for democracy.
Reuters cited U.S. officials as saying that there were reports from the region suggesting that members of al-Qaida's north Africa-based affiliate, known as Al-Qaida in the Islamic Maghreb, may have been involved.
The attack on the Libyan consulate, as it happened
On Wednesday, Obama vowed to catch those responsible for the attack and said he had ordered an increase in security at U.S. diplomatic posts around the globe following the assault.
"The United States condemns in the strongest terms this outrageous and shocking attack," Obama said, while insisting it would not threaten relations with Libya's new government. ... And make no mistake, we will work with the Libyan government to bring to justice the killers who attacked our people."
Zoubeir Souissi / Reuters
The U.S. Ambassador to Libya and three other Americans were killed after protesters angry over a film that ridiculed Islam's Prophet Muhammad stormed the U.S. consulate in the eastern Libyan city of Benghazi, as protests spread across the region.
Doctor tried to save ambassador's life
Ziad Abu Zaid, the duty doctor in the emergency room at Benghazi Medical Center on Tuesday, said Stevens was alive when he arrived at the hospital.
"He came in a state of cardiac arrest. I performed CPR for 45 minutes, but he died of asphyxiation due to smoke inhalation,” he said.
Stevens' body was later returned to U.S. custody at Benghazi airport, a senior U.S. official said. Images of Stevens, purportedly taken after he died, circulated on the Internet. One showed him being carried, with a white shirt pulled up and a cut on his forehead.
Smith died inside the consulate building and the two other Americans died when a squad of U.S. troops sent by helicopter from Tripoli to rescue the diplomats came under mortar attack, said Captain Fathi al-Obeidi, commander of a Libyan special operations unit ordered to meet the Americans.
Obama: Egypt not an ally of US, but not an enemy
Witnesses said the mob at the consulate included tribesmen, militia and other gunmen. Hamam, a 17-year-old who took part in the attack, said Ansar al-Sharia cars arrived at the start of the protest but left once fighting started.
"The protesters were running around the compound just looking for Americans, they just wanted to find an American so they could catch one," he told Reuters. "We started shooting at them, and then some other people also threw hand-made bombs over the fences and started the fires in the buildings."
"There was some Libyan security for the embassy outside but when the hand-made bombs went off they ran off and left," he added.
Hamam said he saw an American die in front of him in the mayhem that ensued. He said the body was covered in ash.
Reuters contributed to this report.
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