WASHINGTON (AP) -- The Bush administration accused Iran and Syria on Friday of fueling ongoing violence in Lebanon by inciting members of the radical Hezbollah movement to take up arms against the Western-backed government.

As Hezbollah militants seized control of large parts of Beirut, the administration denounced the show of force and reaffirmed its support for Prime Minister Fuad Siniora's shaky coalition.

"Backed by Syria and Iran, Hezbollah and its allies are killing and injuring innocent citizens and undermining the legitimate authority of the Lebanese government and the institutions of the Lebanese state," Secretary of State Condoleezza Rice said in a statement.

State Department spokesman Sean McCormack said the United States had evidence that Iran and Syria had taken an active role in encouraging the violence that has killed at least 14 people and wounded 20.

A senior State Department official later identified three former pro-Syrian government ministers as "fully owned subsidiaries of Syria" who took to the airwaves Friday in support of Hezbollah. The official, who spoke on condition of anonymity because of the delicacy of the situation, added that U.S. analysts did not believe Hezbollah would have started the fight without "some kind of green light from Iran."

The State Department is considering how to protect an estimated 50,000 U.S. citizens in Beirut if conditions worsen, although it is assumed that many would not choose to leave because they hold dual nationality and have families in Lebanon.