Shots have been fired outside a British embassy compound in the Iranian capital, Tehran, the third such incident this month.
More shots at the British embassy in Tehran have been reported
Two shots were fired on Sunday evening, but no one was injured, according to an embassy spokesperson.
The embassy itself was closed to the public 10 days ago, after an earlier shooting incident.
No group has claimed responsibility for any of the attacks, which Iranian officials had earlier described as illogical and unacceptable.
Last Tuesday, three or four shots were fired from the street at the British embassy by two men on a motorbike, witnesses said.
The attacks come amid a severe strain in relations between London and Tehran over the arrest in Britain last month of a former Iranian ambassador to Argentina.
Hadi Soleimanpur was arrested in England following an extradition request from Buenos Aires, which accuses him of taking part in a 1994 bombing of a Jewish centre in Argentina that killed 85 people.
He was later freed on bail.