Update 8:21 ET. Two Slain Americans Identified:
Two of the security personnel who were killed Tuesday along with Ambassador Chris Stevens and Information Management Officer Sean Smith have been identified. They are Tyrone S. Woods and Glen A. Doherty, both security personnel who died helping protect their colleagues. Both men were former Navy SEALs, according to a statement from U.S. Secretary of State Hillary Clinton.
Here's more from the statement:
"Tyrone's friends and colleagues called him 'Rone,' and they relied on his courage and skill, honed over two decades as a Navy SEAL. In uniform, he served multiple tours in Iraq and Afghanistan. Since 2010, he protected American diplomatic personnel in dangerous posts from Central America to the Middle East. He had the hands of a healer as well as the arm of a warrior, earning distinction as a registered nurse and certified paramedic. All our hearts go out to Tyrone's wife Dorothy and his three sons, Tyrone Jr., Hunter, and Kai, who was born just a few months ago.
"We also grieve for Glen Doherty, called Bub, and his family: his father Bernard, his mother Barbara, his brother Gregory, and his sister Kathleen. Glen was also a former Navy SEAL and an experienced paramedic. And he put his life on the line many times, protecting Americans in Iraq, Afghanistan, and other hotspots. In the end, he died the way he lived – with selfless honor and unstinting valor."
Update 2:25 ET. Four In Custody:
NPR's Dina Temple-Raston says Libyan officials have informed the U.S. that four people are in custody in connection with the attack on the American consulate in Benghazi that killed Ambassador Chris Stevens and three other embassy staffers on Tuesday.
But U.S. officials have yet to interview the detainees, described as "militants" or to verify their involvement in the attack. She says it is also unclear whether those arrested are Libyans or foreigners.
Here's our earlier post:
Violence sparked by an anti-Islam film and video clip has spread from Libya and Egypt to Yemen today, with protesters in the capital Sanaa storming the U.S. Embassy compound.
Chanting "death to America," the Yemeni protesters broke through a security forces cordon and marched toward the embassy. The protesters reportedly got through the main gate but not into the embassy building itself.
Meanwhile, clashes continued near the U.S. embassy in Egypt, and a U.S. Marine anti-terrorist team has been dispatched to secure U.S. diplomatic facilities in Libya, where an attack earlier this week took the life of Ambassador Chris Stevens.
In Sanaa, protesters removed the embassy's sign on the outer wall and set tires ablaze, The Associated Press reports. Once inside the compound, they brought down the U.S. flag and burned it, the news agency says.
Iona Craig, a reporter from The Times of London who was outside the embassy in Yemen, told NPR that it initially appeared that security forces allowed the hundreds of protesters to break the cordon.
Once protesters got about 60 meters beyond the cordon, security forces fired warning shots with AK-47s and machine guns. "Then everybody ran in panic," she said.
Witnesses say security forces have since restored calm at the embassy. Yemeni news agencies report that U.S. embassy staff had already been evacuated by the time violence broke out.
The anti-Islam film The Innocence of Muslims, produced in the United States and seen mostly via a trailer posted on YouTube, is the proximate cause of the unrest.
On Thursday, Secretary of State Hillary Clinton said the United States government had nothing to do with the "disgusting and reprehensible" film, which she called a cynical attempt to "denigrate a great religion and to provoke rage." However, Clinton emphasized that the U.S. would never stop Americans from expressing their views.
Authorities in Afghanistan have gone so far as to shutdown access to YouTube "indefinitely" to keep Afghans from seeing the film they say insults the Prophet Muhammad, according to NPR's Soraya Sarhadi Nelson in Kabul. Authorities hope blocking the website will help prevent outbreaks of the violence. But she says the Internet provider has yet to receive official notification of the request to block the website and that it is still accessible.
NPR's Leila Fadel, reporting from Cairo, says protesters there seemed to be less concerned about the film and more intent on provoking police, who were seen as a tool of oppression under the past autocratic regime of President Hosni Mubarak.
She says armored vehicles and riot police tried to disperse a crowd of a few hundred young men at the U.S. embassy compound there. Protesters were forced back into nearby Tahrir square and side streets by police using tear gas to disperse the crowd, Fadel says.
NPR's Tom Bowman reports that more than 50 U.S. Marines have arrived in Tripoli to take up security duties at the American embassy, which has been reduced to emergency staffing levels after the consulate in Benghazi was attacked by armed assailants, killing the ambassador and three other diplomatic staff.
He says diplomatic posts around the world have been asked to review security procedures.
A senior administration official says there was a recent security review for the American consulate in preparation for the anniversary of the Sept. 11, 2001, terrorist attacks, according to Bowman. But the official told reporters there was no indication of a heightened threat that would call for more security personnel.
UPDATE at 12:50 ET:
Attorney General Eric Holder, speaking today in Qatar, says the FBI has opened an investigation into the deaths of the ambassador and the three other embassy personnel in Benghazi.
In Egypt, NPR's Fadel reports that the political wing of the Muslim Brotherhood says "peaceful demonstration" against the film is the duty of all Egyptians - both Muslim and Christian. The party called on protesters to contain their anger.