He certainly caused CHAOS!

Well, that’s one way famous folk can create a night to remember… turning up unannounced at a high school prom.

That’s exactly what Justin Bieber did on Saturday night – and needless-to-say he created quite a stir.

Justin, 21, showed up wearing a black-brimmed hat and immediately hit the dancefloor. Understandably, ecstatic prom-attendees at the Chatsworth Charter High School in Los Angeles have since been sharing their excitement on social media. “THANK YOU @justinbieber FOR THE BEST PROM,” said one Twitter user.

Another declared: “I DANCED WITH @justinbieber AT MY PROM.” And with the hashtag #ccshprom soon trending, even the school’s official Twitter account weighed in, saying: “Justin Bieber showing up at our prom? I think we know who had the best prom this year.” The star, who has 63m followers, quickly replied expressing his thanks, explaining attending one had long been a dream.

Pupil Stefany Magadan tweeted directly at the star, apologising because he got “trampled by everybody”. “Definitely going down in history,” she added.

Apparently, Justin was recording music at the same venue Chatsworth High rented out for their end-of-year soiree, and the Canadian singer couldn’t resist joining in on the fun.

He was accompanied by his close friend and rumoured love-interest Hailey Baldwin, as well as model Gabby Westbrook, and songwriter Jason 'Poo Bear' Boyd.

 Hailey Baldwin also attended the high school prom