Iran's judiciary says that about 465 people are still being detained across the country for taking part in a wave of antigovernment protests that began nearly three weeks earlier.
Judiciary spokesman Gholamhosein Mohseni-Ejei also acknowledged that 25 people were killed in violence surrounding the protests that began on December 28.
Tehran prosecutor Abbas Jafari Dolatabadi said 440 "arrested rioters" had been released from detention facilities in Tehran alone in recent days.
Mohseni-Ejei said there were still 55 people being held in the Iranian capital.
He also said that 25 "ordinary citizens and our own forces were killed during the recent troubles," and claimed that none were killed by gunfire from security forces because "they were ordered not to use their weapons."
Officials had previously said 21 people were killed.
Mohseni-Ejei did not provide details on how the members of the security forces or civilians were killed, including six protesters who died while trying to storm a police station in the central province of Isfahan.
An Iranian reformist lawmaker, Mahmud Sadeghi, said last week that about 3,700 people had been arrested across the country during the weeks of protests, which were sparked by anger about Iran's troubled economy and official corruption but escalated rapidly with some calling for the overthrow of the country's clerical rulers.
Iran's parliament said on January 7 that low-level protesters, particularly students, were to be released in waves while protest leaders would be punished.
Hamid Shahriari, deputy head of Iran's judiciary, said last week that antigovernment protest leaders should be handed the "maximum penalty" under Iranian law for organizing what the Islamic Revolutionary Guards Corps has repeatedly described as acts of "sedition."
The death penalty is the most severe sentence imposed by courts in Iran, where it can be applied for a range of crimes including treason, murder, and drug trafficking.