Washington (CNN) -- The U.S. ambassador to Syria, Robert Ford, was safe Thursday after being attacked by a pro-government group, a U.S. government official told CNN.
"It was an attack by an armed mob and he is OK," said the official, who was not authorized to speak to the media and did not want to be named.
Ford, who has been outspoken against the Syrian government's use of violence against protesters, is seen by pro-government supporters as an activist more than a diplomat.
Ford sparked a diplomatic firestorm in July when he traveled to the restive city of Hama to express support for demonstrators. He was welcomed with flowers by local residents who had suffered a brutal crackdown by government forces. President Bashar al-Assad's government called the trip an attempt to foment dissent.
Since then, Ford has continued to be seen by some as serving as a traditional diplomat and more as a provocateur.
A crowd tried to assault Ford and embassy colleagues "as they went about doing the normal work of any embassy," State Department spokesman Mark Toner said.
"The mob was violent; it tried, unsuccessfully, to attack embassy personnel while they were inside several embassy vehicles, seriously damaging the vehicles in the process," Toner said.
Syrian security officers helped secure a path back to the U.S. Embassy for the ambassador and his staff.
U.S. Secretary of State Hillary Clinton condemned we she described as "an unwarranted attack" when Ford and his aides were conducting "normal embassy business."
Clinton said it was an "inexcusable assault" that is "clearly part of an ongoing campaign of intimidation."
At the time of the attack, Ford was visiting Hassan Abdul Azim, head of the opposition Arab Socialist Democratic Union.
According to Azim, about 50 to 100 people gathered at the door to his office and began to chant loudly when Ford arrived. Some of them even tried to break down the door, he said.
The crowd protested rowdily for more than two hours, he said.
Azim could not confirm what Ford was attacked with, but a witness said the demonstrators threw tomatoes.
Azim added that tomatoes were cleaned up off the street afterward.
During their meeting, Azim told Ford that his party doesn't want outside intervention in Syria's unrest, but it does want freedom, democracy and peaceful coexistence among all religious groups.
Ford's outreach to the Syrian opposition has infuriated Syrian government officials. The official Syrian news agency, SANA, citing comments made Monday by Toner, accused the United States of encouraging armed opposition groups to carry out acts of violence against the Syrian army.
Monday, Toner told reporters in Washington that "the (Syrian) government's continued use of violence against innocent civilians, I think, is engendering the opposition to use violence back at the Syrian authorities. ... It's a matter of self-defense."
Meanwhile, the spokesman for the French Embassy in Washington, Luis Vassy, told CNN that the French ambassador to Syria was attacked a few days ago with eggs and stones by pro-government demonstrators after he met with the Greek Orthodox patriarch in Damascus.
France protested the attack. Nobody was injured, but Vassy called the incident "obviously unacceptable."
"We hold the Syrians responsible of the security of our personnel in Syria," Vassy said.
During the summer, the French Embassy in Damascus was attacked by people entering the precinct, and embassy guards had to fire warning shots, Vassy said.
CNN's Ben Brumfield, Tracy Doueiry and Ivan Watson contributed to this report.