Sexual predators and other bad actors have found an easy access point into the lives of young people: They are meeting them online through multiplayer video games and chat apps, making virtual connections right in their victims’ homes.

The criminals strike up a conversation and gradually build trust. Often they pose as children, confiding in their victims with false stories of hardship or self-loathing. Their goal, typically, is to dupe children into sharing sexually explicit photos and videos of themselves — which they use as blackmail for more imagery, much of it increasingly graphic and violent.

Reports of abuse are emerging with unprecedented frequency around the country, with some perpetrators grooming hundreds and even thousands of victims, according to a review of prosecutions, court records, law enforcement reports and academic studies. Games are a common target, but predators are also finding many victims on social platforms like Instagram and Kik Messenger.