Dozens of girls were poisoned today at several schools in Iran, which has been rocked for four months by a mysterious case of poisoning of schoolgirls, according to local media.

Since the end of November, many schools in Iran, the majority of which are girls’ schools, have been hit by sudden poisonings from gas inhalation or other toxic substances, causing nausea and fainting and in some cases requiring hospitalization.

The head of the national investigation committee on the case, MP Hamidreza Kazemi, announced today on state television that the final finding on the case will be published in two weeks.

At least “60 female students were poisoned today in a girls’ school” in Khuzestan province, the Iribnews agency reported, citing a local official. Female students were also poisoned in six schools in a city in northwest Iran, according to the same source, while an unknown number of female students were victims of gas poisoning at a primary school in western Azerbaijan.

According to an official tally of March 7, “more than 5,000 schoolgirls had been poisoned in 230 educational institutions in 25 of Iran’s 31 provinces.

The incidents stopped in early March after dozens of arrests were announced, but resumed three weeks later.

Iran’s Supreme Leader Ayatollah Khamenei had called on March 6 for the imposition of severe penalties, up to and including the death penalty, for those found guilty.

The incidents began two months after the start of the protest movement sparked in Iran by the death on September 16 of Mahsha Amini, the 22-year-old who had been arrested by Iran’s morality police enforcing the Islamic Republic’s dress bans on women.