Tehran's public prosecutor on Wednesday ordered the immediate release of nine students jailed during pro-democracy protests in June and July, the official IRNA news agency said.

The students, thought to be among several dozen arrested during the street protests, were to be freed in accordance with an order Tuesday by Supreme Leader Ayatollah Ali Khamenei for the judiciary to show leniency to jailed students, IRNA said.

Judiciary officials have said that 4,000 people were arrested in the demonstrations in which hundreds of people took to the streets to protest against Iran's clerical leaders.

More than half of those arrested were quickly released but legislators said this week that at least 30 students were being held in Tehran's Evin prison from the recent protests.

The nine students to be freed were part of a "first stage" of releases, IRNA said quoting an unnamed spokesman from the Public Prosecutor's office.

Among the nine were Mehdi Shirzad, son of a reformist parliamentarian, and prominent student leaders Abdollah Momeni and Reza Ameri Masab.

Local analysts said the move to release students indicated an effort by Iran's ruling clergy to ease lingering social tensions in the wake of the protests and wave of arrests.

University students have been at the forefront of protests against Iran's clerical leadership in recent years, staging occasional rallies and protests calling for the release of political prisoners and greater freedom of speech.

But they have paid a high price for their political activism. Many student leaders remain behind bars after being arrested during street demonstrations in 1999. Other have fled the country.