Johansson's butt-pic-leak man is sorry now

A man who faces a possible 121-year jail sentence for leaking a pic of Scarlett Johansson's naked bum cheeks - amongst other things - is all apologetic now he's been caught, claiming he became "addicted to seeing behind the scenes".

Christopher Chaney, 35, of Jacksonville, Florida was arrested and charged on Wednesday after an FBI investigation, following complaints from curvy celebrities that personal stuff they wanted kept secret was appearing in dark corners of the Interweb.

Some of the best purloined pics were of Scarlett Johansson's buttocks as the Match Point star shot her rounded rump herself using her mobile phone and a mirror.

Johansson was one of more than 50 victims, of the hacker, the FBI said, as it lifted the lid on what it called "Operation Hackerazzi".

Chaney faces 26 charges of accessing and damaging computers, wiretapping and identity theft and could face a ludicrous 121 years in prison.

"It started as curiosity and it turned into just being addicted to seeing behind the scenes of the lives of the people you see on the big screen every day," Chaney confessed to reporters.

Chaney managed to get sent copies of emails from accounts he'd hacked into and while he dod not profit from materials he got hold of, his victims were often perturbed and distressed to find their intimate photos or messages outed for all to see.

Chaney said it was a "relief" he finally been caught. "I deeply apologise," he said. "I know what I did was probably one of the worst invasions of privacy. I know it was wrong and have to face it and go forward."

He is expected to appear in court in Florida today.