Iran on Sunday issued its first death sentence linked to participation in "riots", weeks into protests sparked by the death of a woman in morality police custody, the judiciary's website said.

The unidentified accused was sentenced in a Tehran court to death for the crimes of "setting fire to a government building, disturbing public order, assembly and conspiracy to commit a crime against national security," as well as for being "an enemy of God and corruption on earth", Mizan Online reported.

The latter is one of the most serious offences under Iranian law.

Nationwide unrest has followed the September 16 death of Mahsa Amini, 22, after her arrest by the morality police in Tehran for allegedly violating Iran's strict dress code for women.

Dozens of people, mainly demonstrators but also security personnel, have been killed during the protests, which the authorities have branded as "riots".

Another court in Tehran sentenced five others to prison terms of between five to 10 years for "gathering and conspiring to commit crimes against national security and disturbing public order", Mizan said.

All those convicted can appeal their sentences, the website added.

Earlier this month, 272 of Iran's 290 lawmakers demanded that the judiciary apply "an eye for an eye" retributive justice against those who "have harmed people's lives and property with bladed weapons and firearms".

On Sunday, Mizan and other local media also said the judiciary has charged more than 750 people in three provinces for involvement in "recent riots".

Over 2,000 charged

In excess of 2,000 people had already been charged, nearly half of them in the capital Tehran, since the demonstrations began, according to judiciary figures.

Judicial chief for the southern province of Hormozgan, Mojtaba Ghahremani, said 164 people had been indicted, Mizan Online said.

They face accusations including "incitement to killing", "harming security forces", "propaganda against the regime" and "damaging public property", the website said.

It added that their trials would begin "from Thursday in the presence of their lawyers".

Another 276 people were charged in the central province of Markazi, its judiciary chief Abdol-Mehdi Mousavi was quoted as saying by state news agency IRNA.

However, 100 young people were released after signing pledges not to participate in any future "riots", IRNA said.

In the central province of Isfahan, judicial chief Asadollah Jafari said 316 cases had been filed in connection with the recent strife.

Twelve have already gone to trial, the Tasnim news agency reported him as saying late Saturday.

Authorities have denied claims by rights groups abroad that about 15,000 people have been detained in the unrest after Amini's death.

Also on Sunday Iran criticised a Friday meeting between French President Emmanuel Macron and opponents of the Islamic republic, calling his comments after the encounter "regrettable and shameful".

Macron met with four prominent Iranian dissidents, all of them women, and then spoke of his "respect and admiration in the context of the revolution they are leading".

Against the backdrop of the nationwide unrest after Amini's death, dozens have also been killed the southeastern province of Sistan-Baluchistan which borders Pakistan.

Violence in the provincial capital Zahedan erupted on September 30, and authorities say six members of the security forces were among the dead.

Some local figures said the protests in Zahedan were triggered by anger over the reported rape of a teenage girl by a police officer.

Overseas-based activists accused security forces of firing on demonstrators in one of the few Sunni-majority cities in predominantly Shiite Iran.

A delegation from Iran's supreme leader Ayatollah Ali Khamenei expressed sadness and promised solutions in a weekend visit to Zahedan, official media said.

The city's police chief and the head of a police station had already been dismissed, local officials had already announced.