Dozens of schoolgirls were poisoned Saturday in several schools across Iran, local media reported, in continuation of the mysterious phenomenon that has shaken the country for months.

Since late November many schools, mostly for girls, have been affected by sudden poisoning incidents from gases or toxic substances, in some cases causing fainting and hospitalisation among the students.

At least "60 students were poisoned in a girls' school in the town of Haftkel" in the oil-rich southwestern province of Khuzestan, state television's IRIB news agency cited a local official as saying.

A number of schoolgirls were poisoned in "five schools in Ardabil in the northwest", where the victims showed symptoms of "anxiety, shortness of breath and headaches", a provincial medical official told the news agency.

In the northwestern town of Urmia, capital of West Azerbaijan province, "a number of schoolgirls were taken to hospital on Saturday after feeling sick", ILNA news agency reported without further elaboration.

According to an official count provided on March 7, "more than 5,000 students" have been affected by similar poisonings in more than 230 establishments, located in 25 of the country's 31 provinces.

On Friday MP Hamidreza Kazemi, the head of the national fact-finding committee formed to investigate these cases, specified that "the final report" would be published "in two weeks".

"We have received reports from various bodies and we are studying the issue in order to present our conclusion to parliament," he was quoted as saying by state television.

Iran's Supreme Leader Ayatollah Ali Khamenei had called on March 6 for "severe sentences" up to the death penalty against those found responsible for the poisonings, which he described as "unforgivable crimes".

The poisoning cases began two months after the start of a protest movement in Iran sparked by the September 16 death in custody of Mahsa Amini, 22, following her arrest for allegedly violating the strict dress code for women.