Iranians began nationwide celebrations to commemorate the anniversary of the 1979 Islamic revolution.
State television on Thursday aired footage of rallies in Tehran and other cities and towns across the country, many of them in frigid winter weather conditions.
The demonstrators chanted traditional slogans against the US and Israel, and the streets in many cities were decorated with anti-US and anti-Israeli banners and posters.
The rallies commemorate February 11, 1979, when followers of Ayatollah Ruhollah Khomeini ousted US-backed Shah Reza Pahlavi.
The US had helped orchestrate the 1953 coup that overthrew Iran’s popular prime minister, Mohammad Mossadegh, and brought Pahlavi to power.