Sheriff's officials in Santa Clarita on Thursday were investigating a rash of nude photographs of teenage girls and boys being uploaded to a Twitter account.
It began on Wednesday, when a Twitter account called "The Scv Purge" appeared and quickly gained hundreds of followers.
The account holder allegedly posted dozens of full body shots of local teenagers and then threatened release their names at midnight, authorities said.
One teenager, who wanted to remain anonymous, said the account encouraged followers to "expose anyone you know."
The account coincides with Friday's release of the film, "The Purge: Anarchy."
The account was removed by authorities, but whoever was responsible could ultimately face felony charges, said Sgt. Brian Hudson of the Los Angeles County Sheriff's Department.
But for the teenage victims of the Twitter prank, the consequences could be irreparable.
"You have to realize that once they send that photo off ... they have now lost control of the photograph and it is out there ... forever," Hudson said.