Syria urged to protect US diplomats after attack

US Secretary of State Hillary Clinton is demanding that Syria "take every possible step" to protect American diplomats after supporters of President Bashar al-Assad tried to attack the US ambassador yesterday.

During a two-hour siege a mob tried to attack the ambassador Robert Ford and other embassy staff while they visited the Syrian opposition leader, seriously damaging US vehicles and "pelting" the visitors with tomatoes.

No one was injured in the attack and all were returned safely to the embassy after Syrian security officers finally came to their aid and cleared a path out of the building.

A spokesperson for Hilary Clinton has accused President Assad's regime of being behind the incident in what he said amounts to a campaign aimed at intimidating US diplomats as they carry out their duties.