Observers believe Iran's regime, including Revolutionary Guards, may be behind organophosphate poisoning of schoolgirls in cities such as Qom and Boroujerd.
Since late November, hundreds of cases of respiratory poisoning have been reported among schoolgirls, mainly in the holy city of Qom, with some requiring hospital treatment.
Dozens of schoolgirls in Iran were hospitalised on Tuesday after a mysterious poisoning, the latest in a spate of suspected attacks in the Islamic republic.