LOS ANGELES (CBS) — A Florida man is expected to enter a guilty plea in a Los Angeles federal court Monday to charges of hacking into the email accounts of celebrities including Scarlett Johansson, Christina Aguilera, and Mila Kunis.

Christopher Chaney, 35, of Jacksonville, Fla., faces up to 60 years in prison for unauthorized computer access, wiretapping and other felony charges contained in a criminal indictment.

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The case, which allegedly involves as many as 50 victims, was dubbed “Operation Hackerazzi.”

Investigators believe Chaney, who was arrested in October, used publicly available information about celebrities to gain access to their email accounts.

The indictment alleges Chaney had incoming messages forwarded to a separate account he controlled, giving him access to private information, such as email text and file attachments.

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Investigators say the wiretapping allowed Chaney to continually receive victims’ emails even after a password had been reset.

According to the FBI, Chaney offered photos he obtained illegally for sale to various celebrity gossip websites.

Among the images that were eventually posted online were nude photographs of Scarlett Johansson. The actress told “Vanity Fair” the photos were taken for her now ex-husband, actor Ryan Reynolds.

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