Rihanna was rushed to the hospital in Switzerland after performing to a sell-out crowd at Zurich’s Hallenstadion Arena, though why the singer needed to be hospitalized wasn’t made clear, according to PopCrunch.

“Rihanna arrived at the accident and emergency unit. We’re not going to give any details,” a medical center rep says. After roughly two and half hours of treatment, the singer was released and was able to perform in France the next night.