Since November, over 1,000 Iranian schoolchildren have apparently been poisoned by toxic gases in their classrooms, and it seems the attacks are on the rise. An investigation by FRANCE 24's Observers team shows 26 schools were targeted on Wednesday, the highest figure in a single day. It is not known who is behind the poisonings, or indeed why. But what is clear is the impact: girls struggling to breathe, fatigued and nauseous, with many ending up in hospitals.
Produced by Juliette Laurain, Sara Ayach and Imen Mellaz