Thousands of Iranians have been chanting “Death to America” on the anniversary of the 1979 seizure of the US Embassy.
Although President Hassan Rohani has been trying to ease tensions with Washington over Tehran’s nuclear programme, many people use this date to denounce a “nest of spies”.
The rally outside the former embassy complex is an annual rite in Iran but took on extra resonance this year as a barometer of hardline conservative opposition to Rohani’s diplomatic opening to the West after eight years of increasing confrontation under predecessor Mahmoud Ahmadinejad.
Many hardliners say recent revelations about US spying prove that American embassies are places of espionage.
The 1979 siege began when, 10 months after the fall of the US-allied Shah of Iran, radical students stormed the embassy, taking hostage 52 staff for an eventual 444 days.
There have been no US-Iranian diplomatic relations since.