The FBI said the man who allegedly stole private, nude photos from Hollywood celebrities' cell phones and distributed them on the Internet, acted alone.

Christopher Chaney was fingered in a multi-count indictment Wednesday in a press conference announcing the arrest, which resulted from an investigation the FBI dubbed Operation “Hackerazzi.”

"This morning we arrested a Florida man who illegally accessed dozens of email accounts," U.S. Attorney Andre Birotte, Jr. said." Unfortunately, a lot of what he accessed was nude photographs which were then uploaded to the Internet."

Chaney, who was the only individual named in the indictment, went by three aliases in his alleged hacking scheme -- "trainreqsuckswhat," "anonygrrl," and jaxjaguars911" -- according to court papers.

Chaney allegedly "gained unauthorized access of over 50 individuals" according to the indictment, which went into detail about exactly how Chaney accessed and disseminated information from the alleged victims' cell phones.

Among the individuals whose accounts were allegedly breached are the actresses Scarlett Johansson and Mila Kunis, and singer Christina Aguilera.

All three have had private photos hit the Web in the past 12 months.

Private cell phone snaps Johansson, 26, allegedly took of herself surfaced on the Internet in September. One photo showed the "Iron Man 2" actress wearing nothing but a towel, taking a photo of her exposed backside reflected in a mirror. Another photo showed the Golden Globe-winning actress in a topless self-portrait.

“Just because you’re in the spotlight, or just because you’re an actor or making films or whatever, doesn’t mean that you’re not entitled to your own personal privacy,” Johansson said after the photos were made public. “I think no matter what the context, if that is besieged in some way, it feels unjust. It feels wrong."

Birotte, Jr. said the FBI had a "positive working relationship with several victims who agreed to be named in order to bring awareness to cyber hacking" but that the celebrity status of some of the alleged victims had "no basis on the investigation."

Three months ago, hackers released nude photos they claimed were of Blake Lively. Lively's rep denied the photos were of the actress and threatened to sue any web site that published the photos.

Lively was not named in the court documents.

If convicted, Chaney faces maximum 121 years in federal prison, with a mandatory minimum of two years.