Thousands of demonstrators have marched through the Iranian capital as they marked the anniversary of the seizure of the U.S. Embassy in Tehran 36 years ago.
On November 4, 1979, radical Islamic students stormed the embassy compound and held 52 Americans hostage for 444 days, leading to a break in bilateral diplomatic relations.
At the annual state-organized rally in Tehran, participants burned the U.S. flag and chanted slogans such as "God damn America."
State prosecutor Ebrahim Raeisi told the crowd that a number of "spies and writers hired by Americans" had been detained, without elaborating.
"Under no circumstances will we allow penetration of Americans in economic, social, and cultural areas," he added.
Similar demonstrations were held in other Iranian cities.
Hard-liners in Iran have been concerned about growing Western influence as several countries in the West are seeking closer business ties with Tehran following a landmark nuclear deal signed with six world powers in July.
Based on reporting by AP and Reuters