More cases of mysterious poisoning of Iranian schoolgirls were reported Sunday in several provinces, local media reported, sparking calls for the authorities to act amid growing concern among parents.

Since late November, hundreds of cases have been reported, mainly in the holy city of Qom south of the capital Tehran, with at least 52 schools targeted, according to an official tally published on Saturday.

Some of the students have required hospitalisation.

The latest spate of poisonings affected several students in two high schools in the western city of Abhar and in the southwestern city of Ahvaz, ISNA news agency said, quoting local health officials.

Schoolgirls at a primary school in the city of Zanjan in the west were also targeted, ISNA added.

More cases were reported in the holy city of Mashhad in the northeast, Isfahan in the centre and Shiraz in the south, according to Mehr and Ilna news agencies.

Dozens of schoolgirls were taken to local hospitals for treatment, the reports said.

On Friday, President Ebrahim Raisi said he had asked the ministers of intelligence and interior to follow up on the poisoning cases, dubbing them "the enemy's conspiracy to create fear and despair" among the people.

Interviewed by the Fars news agency, Deputy Interior Minister Majid Mirahmadi said the "plotters of the poisoning of girls" were seeking "to close the schools".

He added, however, that those behind this action were also trying to spark more protests in the Islamic republic.

Mirahmadi was referring to the protest movement triggered in Iran by the September 16 death in custody of Mahsa Amini, a young ethnic Kurd arrested for an alleged breach of strict dress rules for women.

Mirahmadi said that most of the affected students suffered complications due to "anxiety and stress".

Last week, Iran's Deputy Health Minister Younes Panahi said the poisonings were aimed at shutting down education for girls.

The mystery surrounding the poisonings has gripped Iran, triggering a wave of anger across the country and demand for action from the authorities by worried parents.