Iran's elite Revolutionary Guards said on Sunday opposition leader Mirhossein Mousavi should be put on trial for fomenting the unrest that erupted after the country's June presidential election, a news agency said.

"If Mousavi, (defeated candidate Mehdi) Karoubi and (former president Mohammad) Khatami are main suspects behind the soft revolution in Iran, which they are, we expect the judiciary ...to go after them, arrest them, put them on trial and punish them," said a senior Guards' commander, Yadollah Javani, the official IRNA news agency reported.

Meanwhile, Iran has jailed the head of the Kahrizak detention centre after at least three people died in custody in the southern Tehran prison.

"The head of the centre has been sacked and jailed. Three policemen who beat detainees have been jailed as well," the official IRNA news agency quoted Iran's police chief Esmail Ahmadi-Moghaddam as saying.

Kahrizak was built for jailing violators of Iran's vice laws. A police statement issued on Thursday confirmed that serious violations took place at Kahrizak.

Ahmadi-Moghaddam also confirmed that some post-election detainees had been tortured in Kahrizak prison, which Supreme Leader Ayatollah Ali Khamenei ordered closed in July for "lack of necessary standards" to preserve rights of prisoners.

The June 12 presidential vote plunged Iran into its biggest internal crisis since the 1979 Islamic revolution and exposed deepening divisions in its ruling elite.

Moderate websites reported the death of at least three protesters in Kahrizak, including the son of a top adviser to conservative defeated presidential candidate Mohsen Rezaie.

After Mohsen Ruholamini's death in Kahrizak, Iran's top judge Ayatollah Mahmoud Hashemi-Shahroudi ordered his envoys to visit all "prisons and detention centres".

The centre became the source of even more controversy when two more Kahrizak detainees later died in a hospital. - Reuters