Secretary of State Hillary Clinton has tonight taken part in a traditional gathering at the State Department to celebrate the end of Ramadan.
"No matter how belated we are honouring Eid and the end of Ramadan, this is a cherished tradition here at the State Department and I would like to thank all of you for being here including the many members of the diplomatic corps.
"Tonight our gathering is more sombre than any of us would like. This comes during sad and difficult days for the State Department family. We lost four Americans, they were good and brave men.
"They were committed to the cause of building a brighter future for the people of Libya and we condemn the violence in the strongest terms. Violence against our posts in Benghazi, in Egypt and now in Yemen."
After drawing criticism for appearing to use the attack on the US embassy in Libya for political gain, Mitt Romney has put a softer edge on his talk about the attack, reports MSNBC.
Mr Romney had released a harshly worded statement criticising the administration while the attack was still ongoing and followed that with a press conference denouncing what he called Obama's weak reaction.
Today he has been more level, with MSNBC quoting the presidential hopeful as saying, "As we watch the world today, sometimes it seems that we’re at the mercy of events, instead of shaping events, and a strong America is essential to shape events."
The White House has said that President Obama has called Yemen's president to thank him for his condemnation of the Embassy attack. Mr Obama stressed the need to protect US diplomats.
Barack Obama has reassured employees at the US State Department following the attack on its consulate in Benghazi, Libya, in which the American ambassador and three embassy staff members died.
The President said today he has ordered his administration to do whatever necessary to protect Americans aboard as violence continued at US embassies in the Middle East and Egypt.
Four people have been arrested by Libyan authorities following the attack on the US consulate in Benghazi in which the US ambassador and three embassy staff were killed.
Deputy interior minister Wanis Sharif told Reuters:
Four men are in custody and we are interrogating them because they are suspected of helping instigate the events at the US consulate.
Libyan authorities have made several arrests following the deadly attack on the US consulate in Benghazi, the Deputy Interior Minister has said.
American ambassador Chris Stevens and three of his staff were killed in Tuesday's assault.
We know you dream of a strong, united #Libya. Ambassador Stevens shared your dream. The best way to honor him is to make it real.
The United States and Libya agreed to work together to track down the culprits of Tuesday's deadly attack on the US consulate in Benghazi in which the American ambassador and three staff died.
President Barack Obama spoke with his Libyan counterpart Mohammed Magarief last night and "agreed to work closely over the course of this investigation," the White House said.
A US official told Reuters that the US military was moving two destroyers toward the Libyan coast to give America flexibility for any future action against Libyan targets.
The military was also sending a Marine Corps anti-terrorist security team to boost security in the North African state.
US President Barack Obama has been speaking to the presidents of Libya and Egypt, urging security cooperation.