A man has pleaded guilty to his part in the hacking of the Gmail and iCloud accounts of more than 100 people, many of them female celebrities.

'The Fappening', as it became known, took the internet by storm in September 2014 after nude photographs of actresses Jennifer Lawrence, Kate Upton and Kirsten Dunst and others were released online on internet forum 4Chan.

And while Ryan Collins, from Lancaster, Pennsylvania, has not been connected to posting the photos, or for being directly involved in leaking them, he admitted one count of gaining unauthorised access to a protected computer to obtain information under the Computer Fraud and Abuse Act in Los Angeles on Tuesday.

As a result, he is likely to face 18 months in prison, the U.S. Attorney for the Central District of California said, rather than the maximum sentence of five years.

Collins, 36, sent fake emails that purported to be from Apple or Google between November 2012 and September 2014, and got victims to unknowingly hand over their usernames and passwords.

The process is known as 'phishing' - and allowed Collins to hack into private email accounts to steal personal information, including nude photos and videos.

His is the first arrest in connection with the security breach.

Female celebrities affected by 'The Fappening' hack Show all 5 1 /5 Female celebrities affected by 'The Fappening' hack Female celebrities affected by 'The Fappening' hack Jennifer Lawrence attends the 88th Annual Academy Awards at Hollywood & Highland Center on February 28, 2016 in Hollywood, California. Female celebrities affected by 'The Fappening' hack Ariane Grande < > at SiriusXM Studio on March 14, 2016 in New York City. Female celebrities affected by 'The Fappening' hack Victoria Justice attends Delta Air Lines Toasts GRAMMY Weekend with "Sites and Sounds," A Private Performance and Interactive Evening with GRAMMY Nominated Artist Leon Bridges, at NeueHouse Hollywood on February 12, 2016 in Los Angeles, California. Female celebrities affected by 'The Fappening' hack Kirsten Dunst attends the screening of "Midnight Special" during the 2016 SXSW Music, Film + Interactive Festival at Paramount Theatre on March 12, 2016 in Austin, Texas. Female celebrities affected by 'The Fappening' hack Kate Upton

David Bowdich, assistant director in charge of the FBI's Los Angeles field office, said in a statement: “By illegally accessing intimate details of his victims' personal lives, Mr. Collins violated their privacy and left many to contend with lasting emotional distress, embarrassment and feelings of insecurity.

"We continue to see both celebrities and victims from all walks of life suffer the consequences of this crime and strongly encourage users of Internet-connected devices to strengthen passwords and to be skeptical when replying to emails asking for personal information."