Courts in Iran's capital have handed prison terms of up to 10 years to 400 people arrested at anti-government protests, a judiciary official says.

Tehran's prosecutor-general said 160 "rioters" were sentenced to between five and 10 years, 80 to between two and five years, and 160 to two years or less, the Mizan news agency reported.

Another 70 were fined, Ali Alqasimehr added, without providing any details.

It comes a day after authorities hanged a second man convicted over the unrest.

The judiciary announced on Monday morning that Majidreza Rahnavard, 23, had been executed in public in the north-eastern city of Mashhad.

A Revolutionary Court convicted him less than two weeks ago of the charge of "enmity against God" after finding he had stabbed to death two members of the paramilitary Basij Resistance Force.

Amnesty International said he was subjected to a sham trial and that the judiciary was "a tool of repression sending individuals to the gallows to spread fear and exacting revenge on protesters daring to stand up to the status quo".

Iran has been engulfed by protests against the country's clerical establishment for almost three months.

They erupted following the death in custody of Mahsa Amini, a 22-year-old woman who was detained by morality police in Tehran on 13 September for allegedly wearing her hijab, or headscarf, "improperly".

Authorities have portrayed the protests as foreign-backed "riots" and responded with lethal force.

So far, at least 490 protesters, including 68 children and 62 security personnel have been killed during the unrest, according to the Human Rights Activists' News Agency (HRANA).

It has also reported the arrest of more than 18,200 people in connection with the protests, of whom 3,780 have been identified.

Authorities have not revealed how many have been arrested nationwide.

However, judiciary officials announced in early November that 1,024 people had been charged in connection with the protests in Tehran. They said the suspects were accused of "acts of sabotage", including "assaulting or martyring security guards" and "setting fire to public property".

Last Thursday, authorities in Tehran executed a 23-year-old man convicted of "enmity against God" following what activists said was a grossly unfair trial. Mohsen Shekari was accused of stabbing and wounding a Basij member and blocking a street in the capital in September.

After Majidreza Rahnavard was hanged on Monday, Amnesty International said it had identified at least 20 other people at risk of execution.

According to the group, 11 individuals have been sentenced to death, three have undergone trials on capital charges and are either at risk of being sentenced to death or may have already been sentenced, and six may be awaiting or undergoing trial on capital charges.

The final category includes 26-year-old professional footballer, Amir Reza Nasr Azadani, who a judiciary official in Isfahan province said on Sunday had been charged with "baghi", or "armed revolt".

Mr Nasr Azadani is accused of killing three security personnel in the city of Isfahan during protests on 16 November.

On Monday night, the global football players' union FIFPRO said it was "shocked and sickened" that he was facing a possible death sentence "after campaigning for women's rights and basic freedom in his country".

Prominent former Iran national team player Ali Karimi, who has backed the protests, tweeted: "Do not execute Amir."

Another former member of the national team, Voria Ghafouri, was arrested last month but was later released on bail. (BBC)

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