0917 GMT January 19, 2018
During his weekly press conference, Gholamhosein Mohseni Ejei also acknowledged that 25 people were killed in violence surrounding the protests that began on December 28, IRNA reported.
Among the 465 detainees, 55 people are being held in the capital, he added.
The judiciary spokesman also said that 25 "ordinary citizens and our own forces were killed during the recent troubles," and said 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.
An Iranian lawmaker, Mahmud Sadeghi, said last week that about 3,700 people had been arrested across the country during the weeks of protests.
Iran's Parliament said on January 7 that low-level protesters, particularly students, were to be released while protest leaders would be punished.
The unrest began over economic issues on December 28 but turned more violent. Officials have blamed the enemies for parts of their efforts to destabilize the country.