DAMASCUS - Four gunmen attacked the United States Embassy in Damascus last night but failed to harm any American diplomats before guards killed three of them.
Syrian state television said the attackers tried to detonate a car bomb in front of the embassy but failed.
A Syrian official said allUS diplomats were safe.
A witness said at least one Syrian security guard was killed by the attackers, who shouted religious slogans.
Another spoke of "gunfire, explosions and quite a commotion".
In Washington, State Department spokesman Gonzalo Gallegos confirmed there was an attack "by unknown assailants".
Syrian security forces sealed off the area. Ambulances and firefighting units rushed to the scene, sirens wailing.
The district is home to several foreign embassies, including the Iraqi mission.
Britain's Ambassador to Syria, Peter Ford, told CNN the attack did not appear to be a "major al Qaeda-like operation" but an operation by a small group.
There was no immediate word on the identity of the attackers, but Syrian forces have clashed with Islamic militants several times in recent months.
In June, four gunmen and a guard were killed when Syrian security forces foiled an attack near the premises of state-run television in Damascus.
US-Syrian relations are very tense. The US recalled its ambassador in February last year, expressing "profound outrage" over the assassination of Lebanon's former Prime Minister Rafik al-Hariri in Beirut, which it blames on Syria.
The US increased its criticism of Syria during Israel's 34-day war in July and August with Lebanon's Hizbollah guerrillas, who are supported by Syria and Iran.
Last night's attack came as the US commemorated the fifth anniversary of the September 11, 2001, terrorist attacks on New York and Washington.
In a prime-time television address from the Oval Office to mark the anniversary, President George W. Bush urged Americans to unite behind the "war on terror".
