The head of Iran's powerful Revolutionary Guards warned protesters that Saturday would be their last day of taking to the streets, in the clearest sign that security forces may intensify their already fierce crackdown on widespread unrest, Reuters reported.

"Do not come to the streets! Today is the last day of the riots," Guards commander Hossein Salami was quoted as having said in some of the toughest language used in the crisis.

"This sinister plan, is a plan hatched ... in the White House and the Zionist regime," Salami said, repeating previous claims by regime officials that the unrest was orchestrated by the US and Israel. "Don't sell your honor to America and don't slap the security forces who are defending you in the face."

A wave of unrest has rocked Iran since Mahsa Amini, 22, died on September 16 after her arrest by the morality police in Tehran for allegedly violating the Islamic Republic's strict dress code for women.

The street violence has led to dozens of deaths, mostly of protesters but also members of the security forces.

Iranians have defied warnings similar to Salami’s throughout the popular revolt in which women have played a prominent role. There were more reports of bloodshed and renewed protests on Saturday.

Human rights group Hengaw reported security forces shooting students at a girls' school in the city of Saqez. In another post, it said security forces opened fire on students at a medical university in Sanandaj, the capital of Kurdistan province.

Several students were injured, with one of them shot in the head, Hengaw said.

Late on Saturday, more protests broke out in the Kurdish town of Marivan, according to social media videos which showed demonstrators starting fires on streets as gunshots could be heard.

Earlier this week, Iran indicted 315 people on charges related to the protests, with four of them being indicted on charges of “war against God”, which can carry a death sentence.