Explicit images taken with the photo sharing app Snapchat have reportedly been intercepted via a third party app and leaked online.
Users of the app, many of them teenagers, have apparently had their photos gathered over a number of years before being posted on a website.
The leak - dubbed the 'Snappening' - comes after the iCloud security breach in which nude photos of stars including Jennifer Lawrence and recently former Dr Who Matt Smith were published online.
San Francisco-based Snapchat said it was not the source of the latest leak and that it strictly prohibits use of third party apps, which are created by separate developers as "add-ons".
"We can confirm that Snapchat's servers were never breached and were not the source of these leaks," a spokeswoman said.
"We vigilantly monitor the App Store and Google Play for illegal third-party apps and have succeeded in getting many of these removed."
Snapchat allows users to share videos and images that "disappear" after up to 10 seconds. However, recipients can "screen-grab" and save the pictures if they wish.
The app came under fire earlier this year after hackers published 4.6 million Snapchat user names and phone numbers on a website.
Police and children's charities have previously warned teenagers about the dangers of using the app to send intimate photos.
In last month's so-called 'Fappening' scandal a hacker posted hundreds of naked images of celebrities on the online community 4Chan.
Jennifer Lawrence, one of the most high-profile victims, told Vanity Fair: "It's not a scandal. It is a sex crime."
Other victims include Kim Kardashian, Rihanna, actress Winona Ryder and Matt Smith's ex-girlfriend Daisy Lowe.