Sheriff's detectives have already investigated more than 80 cases this year involving thousands of "nude and compromising photographs and videos" of children and teenagers on the Internet, McDonnell wrote in a letter posted on Facebook.
Last year, he said, a sheriff's task force investigated more than 500 such cases, McDonnell said. One in four photos involved teenagers "who had taken nude 'selfies,'" he wrote.
"All too often, these images end up on the internet or in the hands of child predators, some of whom actually make contact with these children," the sheriff wrote.
"Online forums and websites that market themselves as platforms where these images 'disappear' are very misleading; let me be clear; these images NEVER disappear," he continued. "They are forever present on the internet, viewed and traded like baseball cards by child molesters, predators and extortionists."
McDonnell called on parents and public figures to talk to teenagers and children about the "high-risk consequences" of sharing such images. The production, distribution or possession of images showing sexually explicit conduct involving someone younger than 18 is a federal crime.
The Sheriff's Department has a newly formed task force dedicated to investigating human trafficking. McDonnell said it would pursue online predators of children "to the fullest extent of the law."
Last week, McDonnell told reporters that the task force had rescued 60 victims since it was formed late last year. Many of those victims, the sheriff said, were between 14 and 17.
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