The American ambassador to Libya and 3 officials have been killed after a mob attacked the US consulate.
It happened in the eastern city of Benghazi yesterday.
Christopher Stevens had been in the country for less than 4 months.
The mob was protesting against a film deemed offensive to Islam just hours after Islamists also stormed the US embassy in the Egyptian capital Cairo.
Secretary of State Hilary Clinton says she had spoken with Libyan leaders to help protect Americans working in Libya.
“I called Libyan President Magariaf to coordinate additional support to protect Americans in Libya” she said.
“President Magariaf expressed his condemnation and condolences and pledged his government’s full cooperation”.
“In light of the events…the United States government is working with partner countries around the world to protect our personnel, our missions, and American citizens worldwide” she added.
Mrs. Clinton also condemned the attacks which happened on the anniversary of 9/11.
The two incidents related to what protestors said was a film that insulted Prophet Mohammad.
However it was not clear which film prompted the protests.
Reports say shooting and an explosion was heard from inside the closed-off area around the embassy.
Previous to this posting Mr. Stevens had several diplomatic assignments in the Middle East and North Africa.