The National Bureau of Investigation has issued a warning to parents of underage children who use WhatsApp that there are chat groups on the platform where inappropriate materials for kids are being shared.
The content shared in these groups include pornographic, violent and even child sexual abuse materials (CSAM), according to the law enforcement agency.
The warning was issued to parents of schoolkids in a number of communities in Finland.
According to the NBI, those behind the groups aim to expand the number of users as much as possible.
There are settings in WhatsApp that can prevent unknown contacts from adding users to message groups without their permission. They can be found under the application's privacy settings for groups.
Parents have also been contacted by schools warning about specific groups.
In Vantaa, a message from one school seen by Yle urged parents to talk with their children about the matter and to check their phones to see which chat groups they may belong to on WhatsApp.
According to WhatsApp's terms of service rules, people using the application in the European Economic Area need to be at least 16 years of age, while the minimum age outside Europe is 13.
Would you like a roundup of the week's top stories in your inbox every Thursday? Then sign up to receive our weekly email.
Users with an Yle ID can leave comments on our news stories. You can create your Yle ID via this link. Our guidelines on commenting and moderation are explained here.