The party-goers, all males ages 19 to 22, were taken to Madrid's Puerta del Hierro Hospital Saturday night for treatment of symptoms, including euphoria and increased heart rate, TheLocal.es reported.
One of the Alfonso X University students was found by paramedics in a comatose state and was unresponsive to stimulus.
"One of them brought [the cake] from his village," Jose Dominguez de Posada, the university's dean, told Spanish news agency EFE. "There's no way an incident of this caliber will go unpunished."
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