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Katy Perry surprised a group of students when she gatecrashed their prom for an impromptu performance.
The I Kissed A Girl singer popped into the school dance taking place in her hotel in Australia when she heard the DJ playing her hit single California Gurls, reports Radar Online.
According to the site, the pop star picked up a mic and began singing along to the No 1 hit while the stunned students looked on.
One of the pupils said: "Everyone went nuts and it was the perfect ending to our evening."
Katy, who is engaged to British funnyman Russell Brand, apparently stayed at the bash for about 10 minutes before heading off.
