Some militants stand guard at the gate of the US embassy in Tripoli, Libya, on Aug. 31, 2014. A group of Islamist fighters have stormed the US embassy in Tripoli, as intense fighting is still going on in the capital's suburb, a security source said on Sunday.(Xinhua/Hamza Turkia)

Photo taken on Aug. 31, 2014 shows an interior view of the US Embassy in Tripoli, Libya. A group of Islamist fighters have stormed the US embassy in Tripoli, as intense fighting is still going on in the capital's suburb, a security source said on Sunday.(Xinhua/Hamza Turkia)

Photo taken on Aug. 31, 2014 shows the US embassy in Tripoli, Libya. A group of Islamist fighters have stormed the US embassy in Tripoli, as intense fighting is still going on in the capital's suburb, a security source said on Sunday.(Xinhua/Hamza Turkia)

Photo taken on Aug. 31, 2014 shows the US embassy in Tripoli, Libya. A group of Islamist fighters have stormed the US embassy in Tripoli, as intense fighting is still going on in the capital's suburb, a security source said on Sunday.(Xinhua/Hamza Turkia)

A militant poses for photos at the gate of the US embassy in Tripoli, Libya on Aug. 31, 2014. A group of Islamist fighters have stormed the US embassy in Tripoli, as intense fighting is still going on in the capital's suburb, a security source said on Sunday.(Xinhua/Hamza Turkia)

Two militants talk at the gate of the US embassy in Tripoli, Libya on Aug. 31, 2014. A group of Islamist fighters have stormed the US embassy in Tripoli, as intense fighting is still going on in the capital's suburb, a security source said on Sunday.(Xinhua/Hamza Turkia)

A militant sits outside the building of US embassy in Tripoli, Libya, on Aug. 31, 2014. A group of Islamist fighters have stormed the US embassy in Tripoli, as intense fighting is still going on in the capital's suburb, a security source said on Sunday.(Xinhua/Hamza Turkia)

Some militants stand outside the US embassy in Tripoli, Libya on Aug. 31, 2014. A group of Islamist fighters have stormed the US embassy in Tripoli, as intense fighting is still going on in the capital's suburb, a security source said on Sunday.(Xinhua/Hamza Turkia)