Stewartry schoolgirl was asked to send sexual images of herself via social media.
Police are investigating the shocking incident, which saw the 14-year-old contacted by someone through Snapchat and asked to send the photos.
It comes after a similar incident last month when a primary school pupil was talked into sending similar images.
Sergeant Colin Scott said: “They may not be aware but they are victims of a sexual offence.
“We need to get the message out there. Anyone this happens to should tell an adult they can trust. That might be a parent, relative or guardian but it may also be a police officer or a teacher.
“Parents also need to be taking an interest in what’s happening on their children’s phones.”
The latest incident, which happened on December 11, is now the subject of a police investigation.
Sergeant Scott said that as well as reporting such matters to the police, youngsters and parents can also contact Snapchat on safety@snapchat.com and there is also information on the firm’s online support page.
