Chatsworth Charter High School got an unexpected surprise at their senior prom -- Justin Bieber.

On Saturday, the "Boyfriend" singer made an unexpected appearance at the Chatsworth Charter High School prom held at Jim Henson Studios in Hollywood, California. The students were thrilled when the Biebs cruised onto the dance floor and casually danced with everyone.

Ashley Brooke, who attended the prom with boyfriend Chris Tholee, was Bieber's first dance partner. She tweeted a video clip of her with the celebrity Saturday night along with the caption, "I DANCED WITH @justinbieber AT MY PROM."

The Los Angeles Unified School District was not so thrilled. School administrators claim Bieber physically shoved his way into the event and put everyone at risk, reports TMZ.

School officials allege the pop star and his entourage shoved past security to gain entry to the high school prom. The school board believes the "Confident" singer's surprise dance appearance put students at risk. Administrators were worried they wouldn't be able to control the frenzied crowd.

"His entourage pushed past the school's security to gain access to the dance floor," a district representative told TMZ.

Bieber had been recording on the Jim Henson Studios lot, which is something school administrators say they knew. However, they were "assured that he would not come out to interfere."

Bieber's representative told TMZ that contrary to claims the singer and his crew pushed their way inside the prom, he entered the prom at the request of a couple students he met on the lot and no one tried to stop him.

"It's unfortunate they're trying to make this a negative thing. It was awesome for all the kids," the representative said.

The school does admit the students enjoyed a "once in a lifetime experience," but adds its main concern was for everyone's safety.

The prom ended without anyone injured.