(CNN)Iran has released more than 400 people detained in anti-government protests that broke out across the country in late December, state-run media reports.
Iran releases 440 anti-government protesters, state-run media reports
Twenty-one people died and an unknown number were detained during six days of demonstrations, which were the biggest challenge to the Iranian regime since 2009.
Tehran's Public and Revolution courts prosecutor Abbas Jafari Dolatabadi announced Sunday that 440 detainees had been released, Iran's state-run Islamic Republic News Agency (IRNA) reported.
Dolatabadi also urged the judges to pursue the cases of other rioters and prepare the grounds for their immediate release, IRNA said.
Iran's Judiciary Spokesman Gholam Hossein Mohseni Ejei said "only 55 suspects are still under detention in Tehran now" during his weekly press conference on Sunday in Tehran, according to Iran's semi-official Fars News Agency.
The exact number of detainees across Iran is still unknown.
Lawmaker Mahmoud Sadeghi claimed Tuesday that roughly 3,700 people had been arrested. That number is far higher than the 450 people Iranian authorities previously said were detained after protests began December 28. US officials had put the number held at 1,000.
Tehran member of parliament Sadeghi said 40 to 68 students were among the 3,700 arrested. He added that "due to the fact that several security organizations had made the arrests, it will take some time to give an accurate count," according to the Iranian parliament's news agency.
On Monday, state-run Aftab News reported that 22-year-old student protester Sina Ghanbari died in custody after being held in Tehran's notorious Evin Prison along with hundreds of other protesters.
The University of Tehran was working to track and secure the release of its students who had been detained, according to the semiofficial Iranian Students' News Agency.
National Police spokesman Saeed Montazer al-Mahdi said last Sunday that the majority of those detained had been released on bail, but that "the leaders of the disturbances are being held by the judiciary," the state-run Al-Alam News Agency reported.
The mainly young protesters rallied against President Hassan Rouhani's government, complaining of a stagnant economy, rampant corruption and rising fuel and food prices.
Iran's unemployment rate among those 15 to 29 is well over 24%, according to official statistics -- and even higher among urban youth and women.