Iranian leader Sayyed Ali Khamenei on Monday considered the poisoning of Iranian schoolgirls in recent months an "unforgivable" crime amid the spread of suspected poisoning across the country with hundreds of girls hospitalized.

"Authorities should seriously pursue the issue of students' poisoning. This is an unforgivable crime... the perpetrators of this crime should be severely punished," Sayyed Khamenei was quoted as saying by state media.

Over a thousand Iranian girls in different schools have suffered "mild poison" attacks since November, according to state media and officials.

In most cases, the schoolgirls suffered respiratory problems, nausea, fatigue, and dizziness.

The spreading attacks that started in November in the city of Qom in central Iran have spread to at least 25 of Iran's 31 provinces.

An Iranian official revealed that a suspicious fuel tanker that was found near a school in a suburb of Tehran, after being spotted in two other sites near other schools in Qom and Bourjerd, is suspected to be responsible for the poisoning. The tanker was reportedly apprehended and the driver was arrested.

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Poisoning schoolgirls amounts to crime, inhumane act committed by enemies

On his part, Iranian President Ebrahim Raisi on Sunday underlined that the poisoning of Iranian schoolgirls amounts to a crime and an inhumane act committed by Iran's enemies.

"The enemy’s new conspiracy of creating fear in the hearts of students… and their parents is a crime and an inhumane act," Raisi said in a cabinet session.

The Iranian head of state ordered officials to swiftly investigate the matter and inform citizens about its whereabouts to alleviate their concerns, underlining the importance of pursuing the main culprits and dealing with them seriously.

Raisi pointed out that the poising of schoolgirls is "another link in the chain of the enemy’s plots" aimed at creating chaos in the country, manipulating public opinion, and infusing fear among the students.

On Friday, the Iranian President said he had tasked the ministers of intelligence and interior with pursuing the matter, adding that "through its hybrid war, the enemy sought to create despair among the people. And recently through its psychological war… the enemy sought to create stress and fear among students and parents so as to spark riots."

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