Manitoba RCMP are investigating after a seven-year-old girl was coerced into sending nude photos to a man over Snapchat — an example of what experts and police warn is a growing trend of children under 13 being sexually exploited through social media.

The images and videos being sent through the online messaging app were discovered after the girl's mother went into the child's room. The girl quickly put down a cellphone when her mother came in, according to a production order document obtained by CBC.

When the mother became suspicious and took the phone, she learned the girl had been chatting with an older man.

The mother found pictures of a penis within those chats and contacted RCMP. She gave them the phone for analysis, according to the document.

Police say they found explicit conversations over Snapchat between a man from the United Kingdom and the seven-year-old, as well as images and video shared between the two.