An estimated 400 people have demonstrated for the fourth time in little over a week outside the British embassy in Iran against the actions of US-led forces in Iraq, witnesses say.
A Reuters journalist on Sunday saw at least two firecrackers and several tomatoes thrown at the embassy by the crowd of mostly students as they chanted "Death to Britain, Death to America."
Riot police with batons and shields prevented the crowd from getting close to the main gate of the embassy. About a dozen people were arrested as police tried to disperse the crowd. About 100 of the demonstrators refused to move and staged a sit-in in front of the embassy.
Three protests at the embassy last week turned ugly with demonstrators hurling petrol bombs, firecrackers and stones at the large diplomatic compound in central Tehran. No one was hurt in those incidents.
"The British embassy must be closed down. Its mercenary ambassador must be expelled," the crowd chanted on Sunday.
Shia Muslim Iran has in recent weeks become more vocal in opposing the presence of US-led forces in Iraq. Religious leaders in the Islamic Republic have been particularly incensed by fighting close to holy Shia sites in Najaf and Kerbala.
In a statement on Sunday, the protesters listed several demands, including the expulsion of British Ambassador Richard Dalton, an apology from the United States and Britain for "desecrating" holy sites in Iraq and the immediate withdrawal of US-led forces from Najaf and Kerbala.