Disturbing footage has emerged of up to 80 students convulsing, screaming and fainting at Elsa Perea Flores School in northern Peru's Tarapoto.
Experts are struggling to explain the hysteria that broke out at the school, which was reportedly built on a Mafia graveyard.
Doctor Antony Choy told national channel Panamericana TV: 'We don't understand how this has kept going on.
'We know it started on April 29 and now it is still happening. Now there are almost 80 pupils [still affected].'
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