Iran on Monday executed a second man convicted over the protests that have shaken the regime for almost three months, defying an international outcry over its use of capital punishment against those involved in the movement.

Rights groups had at the weekend warned that several other people arrested over the demonstrations were at imminent risk of being executed.

Majidreza Rahnavard had been sentenced to death by a court in the city of Mashhad for killing two members of the security forces with a knife, and wounding four other people, the judiciary's Mizan Online news agency reported.

It said he was hanged in public in the city, rather than inside prison.

The latest execution came with global outrage still reverberating after Iran on Thursday carried out the first execution linked to the protests.

Mohsen Shekari, 23, was convicted of attacking a member of the security forces. His hanging prompted angry reactions from Europe and the United States.

The weeks of protest were sparked by the death in custody of Mahsa Amini, a Kurdish-Iranian arrested by the morality police for allegedly breaching the Islamic republic's strict dress code for women.

The protests, described by authorities as "riots", represent the biggest challenge to the regime since the shah's ouster in 1979. They have been met with a crackdown that activists say aims to instill public fear.

New sanctions

Prior to the two executions, Iran's judiciary said it had issued death sentences to 11 people in connection with the protests, but campaigners say around a dozen others face charges that could see them also receive the death penalty.

"No due process. Sham trials. That's how they want to stop the nationwide protests," said Omid Memarian, a senior Iran analyst at Democracy for the Arab World Now after the latest execution.

Rahnavard was arrested on 19 November while trying to flee the country, according to Mizan.

Unconfirmed reports gave his age as 23.

"Majidreza Rahnavard's crime was protesting the murder of Mahsa Amini. The regime's method on dealing with protests is execution. EU recall your ambassadors," said US-based dissident Masih Alinejad.

After Shekari was put to death, German Foreign Minister Annalena Baerbock said it showed a "boundless contempt for human life".

Among other reactions, Washington called Shekari's execution "a grim escalation" and vowed to hold the Iranian regime to account for violence "against its own people."

The United Kingdom and Canada imposed additional sanctions on Iran after Shekari's execution.

Iran's use of the death penalty is part of a crackdown that Olso-based Iran Human Rights says has seen the security forces kill at least 458 people.

According to the UN, at least 14,000 have been arrested.

Iran is already the world's most prolific user of the death penalty after China, with more than 500 executions this year alone, according to IHR.

Public executions are highly unusual in Iran.

In July a man who had been convicted over the murder of a police officer in the southern city of Shiraz was hanged in public and IHR said this was the first such public execution in two years.