A U.S. official says the United States has closed its embassy in Libya's capital after evacuating all personnel on a ferry and a chartered airplane.
The official said the Tripoli embassy's operations were suspended because of the deteriorating security situation.
The last embassy staff departed on a chartered flight at 1:49 p.m. EST.
Militias loyal to Gadhafi reportedly opened fire Friday on protesters streaming out of mosques and marching across the Libyan capital to demand the regime's ouster. Multiple deaths were reported.
One man among a crowd of thousands said gunmen on rooftops and in the streets opened fire with automatic weapons and even an anti-aircraft gun.
Diplomats have unanimously condemned Libya, ordered a probe into possible crimes against humanity and recommended the country's suspension from the United Nation's top human rights body.
The U.N.'s top human rights official warned that mass killings in Libya, possibly of thousands, require the world to "step in vigorously" and immediately end a brutal crackdown on anti-government protesters in the North African country.
The U.N. is also considering sanctions that could include an arms embargo and the freezing assets of top government officials.
President Barack Obama issued a statement saying U.S. sanctions against Libya will target Gadhafi's government, while protecting the assets of the people of Libya.
U.S. Treasury Department officials warned U.S. financial institutions to scrutinize accounts held by or for foreign political figures.
The violence has tens of thousands of foreigners trying to flee the country.
A U.S. chartered ferry carrying mostly Americans had been stuck in Tripoli because of rough seas, but it finally left for Malta on Friday.
Gadhafi's crackdown - the harshest by any Arab leader in the wave of protests that has swept the Middle East the past month - has so far helped him maintain control of Tripoli, home to about a third of Libya's 6 million population. But the uprising has divided the country and raised the specter of civil war.
The Associated Press contributed to this report.