Iranian officials say they have released 155 of some 350 people arrested during recent protests by Arab-Iranians in southwest Iran.
Iran's state news agency quotes judiciary officials as saying more prisoners are expected to be released over the next few days. Officials said most of the detainees were under 20 years of age.
At least several protesters were reported killed in clashes with security forces, and the U.S. State Department said Iran violated the human rights of minority groups by arresting protesters.
The unrest in Khuzestan began after some news media publicized a document saying the government planned to move ethnic Arab Iranians from the oil-rich area.
Iran says the document was a forgery. Officials have closed the Tehran bureau of Arabic-language television station al-Jazeera while they conduct an investigation.