U.S. Secretary of State Hillary Clinton responds forcefully to intense questioning on the September attacks on U.S. diplomatic sites in Benghazi, Libya, during a Senate Foreign Relations Committee hearing on Capitol Hill in Washington January 23, 2013. REUTERS/Jason Reed (UNITED STATES - Tags: POLITICS CIVIL UNREST TPX IMAGES OF THE DAY) 

A protester reacts as the U.S. Consulate in Benghazi is seen in flames during a protest by an armed group said to have been protesting a film being produced in the United States September 11, 2012. An American staff member of the U.S. consulate in the eastern Libyan city of Benghazi has died following fierce clashes at the compound, Libyan security sources said on Wednesday. Armed gunmen attacked the compound on Tuesday evening, clashing with Libyan security forces before the latter withdrew as they came under heavy fire. REUTERS/Esam Al-Fetori (LIBYA - Tags: POLITICS CIVIL UNREST TPX IMAGES OF THE DAY) 

A December 21, 2012 email from former U.S. Secretary of State Hillary Clinton is shown in this handout image taken from a State Department press release on May 22, 2015.
The State Department on Friday posted on its website a set of Clinton's emails that were related to a 2012 attack on the U.S. facility in Benghazi, Libya. REUTERS/U.S. State Department/Handout via Reuters ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY. FOR EDITORIAL USE ONLY. NOT FOR SALE FOR MARKETING OR ADVERTISING CAMPAIGNS. THIS PICTURE IS DISTRIBUTED EXACTLY AS RECEIVED BY REUTERS, AS A SERVICE TO CLIENTS 

The U.S. Consulate in Benghazi is seen in flames during a protest by an armed group said to have been protesting a film being produced in the United States September 11, 2012. An American staff member of the U.S. consulate in the eastern Libyan city of Benghazi has died following fierce clashes at the compound, Libyan security sources said on Wednesday. Armed gunmen attacked the compound on Tuesday evening, clashing with Libyan security forces before the latter withdrew as they came under heavy fire. REUTERS/Esam Al-Fetori (LIBYA - Tags: POLITICS CIVIL UNREST) 

The U.S. Consulate in Benghazi is seen in flames during a protest by an armed group said to have been protesting a film being produced in the United States September 11, 2012. An American staff member of the U.S. consulate in the eastern Libyan city of Benghazi has died following fierce clashes at the compound, Libyan security sources said on Wednesday. Armed gunmen attacked the compound on Tuesday evening, clashing with Libyan security forces before the latter withdrew as they came under heavy fire. REUTERS/Esam Al-Fetori (LIBYA - Tags: POLITICS CIVIL UNREST TPX IMAGES OF THE DAY) 

An exterior view of the U.S. consulate, which was attacked and set on fire by gunmen yesterday, in Benghazi September 12, 2012. Christopher Stevens, the U.S. ambassador to Libya, and three embassy staff were killed as they rushed away from the consulate building, stormed by al Qaeda-linked gunmen blaming America for a film that they said insulted the Prophet Mohammad. Stevens was trying to leave the consulate building for a safer location as part of an evacuation when gunmen launched an intense attack, apparently forcing security personnel to withdraw. REUTERS/Esam Al-Fetori (LIBYA - Tags: POLITICS CIVIL UNREST) 

A tear runs down the face of U.S. President Barack Obama as he answers questions about the attack on the U.S. embassy in Benghazi, Libya while Britain's Prime Minister David Cameron listens during a joint news conference in the East Room of the White House in Washington, May 13, 2013. REUTERS/Jim Bourg (UNITED STATES - Tags: POLITICS TPX IMAGES OF THE DAY) 

Kariman Ghali (R), mother of Alber Saber (L), reacts at the cage during his trial in Cairo September 26, 2012. An Egyptian Copt arrested on suspicion of posting an anti-Islam video online that ignited Muslim protests around the world will stand trial next Wednesday on charges of insulting religions, the state news agency MENA said on Monday. Alber Saber was arrested at his Cairo home on September 13 after neighbours accused him of uploading sections of the film "Innocence of Muslims" and making another movie mocking all religions. REUTERS/Mohamed Abd El Ghany (EGYPT - Tags: CIVIL UNREST CRIME LAW) 

Computer science graduate Alber Saber, 27, arrives at his trial in Cairo September 26, 2012. An Egyptian Copt arrested on suspicion of posting an anti-Islam video online that ignited Muslim protests around the world will stand trial next Wednesday on charges of insulting religions, the state news agency MENA said on Monday. Alber Saber was arrested at his Cairo home on September 13 after neighbours accused him of uploading sections of the film "Innocence of Muslims" and making another movie mocking all religions. REUTERS/Mohamed Abd El Ghany (EGYPT - Tags: CIVIL UNREST CRIME LAW) 

Nakoula Basseley Nakoula (C) is escorted out of his home by Los Angeles County Sheriff's officers in Cerritos, California September 15, 2012. Nakoula, a California man convicted of bank fraud has been escorted to an interview with federal officers probing possible probation violations stemming from the making of an anti-Islam video that has triggered violent protests in the Muslim world, police said on Saturday. A Los Angeles County Sheriff's spokesman said Nakoula voluntarily left his home, accompanied by sheriff's deputies, to meet with the officers in the Cerritos Sheriff's Station. The obscure 13-minute English-language video, which was filmed in California and circulated on the Internet under several titles including "Innocence of Muslims," portrays Prophet Mohammad engaged in crude and offensive behavior. REUTERS/Bret Hartman (UNITED STATES - Tags: RELIGION CRIME LAW POLITICS TPX IMAGES OF THE DAY) 

U.S. President Barack Obama and Secretary of State Hillary Clinton deliver remarks during a transfer ceremony of the remains of U.S. Ambassador to Libya, Chris Stevens and three other Americans killed this week in Benghazi, at Andrews Air Force Base near Washington, September 14, 2012. Ambassador Stevens and the other Americans died after gunmen attacked the lightly fortified U.S. consulate and a safe house refuge in Benghazi on Tuesday night. REUTERS/Jason Reed (UNITED STATES - Tags: POLITICS) 

The remains of Americans killed in Benghazi this week are taken off a transport aircraft during a return of remains ceremony at Andrews Air Force Base near Washington, September 14, 2012. President Barack Obama arrived at Andrews Air Force Base on Friday to lead a ceremony honoring the return of the remains of the U.S. ambassador and three other Americans killed in an attack in Libya this week. Ambassador Christopher Stevens and the other Americans died after gunmen attacked the lightly fortified U.S. consulate and a safe house refuge in Benghazi on Tuesday night. REUTERS/Jason Reed (UNITED STATES - Tags: POLITICS) 

Protesters help an injured man, who was hurt during clashes, along a road leading to the U.S. embassy, near Tahrir Square in Cairo September 14, 2012. Egyptian protesters, angry at a film they say insults Prophet Mohammad, hurled stones on Friday at a line of police in Cairo blocking their way to the U.S. embassy, which was attacked earlier this week. REUTERS/Amr Abdallah Dalsh (EGYPT - Tags: POLITICS CIVIL UNREST RELIGION) 

Protesters climb a fence at the U.S. embassy in Sanaa September 13, 2012. Hundreds of Yemeni demonstrators stormed the U.S. embassy in Sanaa on Thursday in protest against a film they consider blasphemous to Islam, and security guards tried to hold them off by firing into the air. Yemen's embassy in Washington said no casualties were reported when the protesters stormed the U.S. embassy compound in Sanaa on Thursday. REUTERS/Mohamed al-Sayaghi (YEMEN - Tags: POLITICS CIVIL UNREST TPX IMAGES OF THE DAY) 

Protesters destroy an American flag pulled down from the U.S. embassy in Cairo September 11, 2012. Egyptian protesters scaled the walls of the U.S. embassy on Tuesday, tore down the American flag and burned it during a protest over what they said was a film being produced in the United States that insulted Prophet Mohammad. REUTERS/Mohamed Abd El Ghany (EGYPT - Tags: CIVIL UNREST POLITICS RELIGION) 

White House staff are pictured after they lowered the U.S. flag to half staff on the roof of the White House in Washington September 12, 2012, following the death of U.S. Ambassador to Libya, Chris Stevens and others in Benghazi. Stevens and three embassy staff were killed in an attack on the Benghazi consulate and a safe house refuge, stormed by Islamist gunmen blaming America for a film they said insulted the Prophet Mohammad. REUTERS/Jason Reed (UNITED STATES - Tags: POLITICS CIVIL UNREST) 

Christopher Stevens, the U.S. ambassador to Libya, smiles at his home in Tripoli June 28, 2012. Stevens and three embassy staff were killed late on September 11, 2012, as they rushed away from a consulate building in Benghazi, stormed by al Qaeda-linked gunmen blaming America for a film that they said insulted the Prophet Mohammad. Stevens was trying to leave the consulate building for a safer location as part of an evacuation when gunmen launched an intense attack, apparently forcing security personnel to withdraw. Picture taken June 28, 2012. REUTERS/Esam Al-Fetori (LIBYA - Tags: POLITICS CIVIL UNREST OBITUARY)