Epperson, 21, and another female kicked a clubgoer's butt at the Colony nightclub early Thursday morning, sources tell TMZ. The alleged victim made a citizen's arrest after complaining of bruising and pain, and said she will press charges against the singer, according to TMZ.
TMZ says Epperson will be booked and transferred to a nearby jail.
The Los Angeles Police Department had no immediate information on Epperson.
An e-mail to Epperson's rep was not immediately returned.
Epperson was eliminated during the semifinals on the seventh season of Idol.