Spend enough time on 4chan's notorious /b/ message board and you'll come across child porn that slipped past overwhelmed moderators. One Navy sailor downloaded some kiddie porn he found on 4chan; now he's the subject of a federal investigation.

Navy sailor Collin Campbell loaned his iPhone to a buddy while they were aboard the USS Boxer so he could play some games. But when his friend opened up a folder called "Porn," he found a number of images that appeared to be child porn. (Note to pedophiles: Do not store your kiddie porn in a folder called "porn".) The friend reported Campbell to the Naval Criminal investigative Service, which launched an investigation.

When questioned, Campbell admitted to "downloading between 10-20 images of child pornography and alleged he obtained all those images from the website www.4chan.org," according to court documents posted by the Smoking Gun. These images, as described in the filing, were extremely explicit, including one featuring a prepubescent girl giving an adult a blowjob.

Child porn is technically forbidden on 4chan, and is subject to censorship by moderators. But it's still surprisingly common on /b/. (Journalist Douglas Rushkoff felt "infected" by it when he waded into 4chan for the Daily Beast.) It's sort of a sick game among the /b/-tards to post threads of child porn ("CP," they call it), then laugh about how the moderators are sleeping on the job.

4chan's founder, Christopher "Moot" Poole, implicitly acknowledged the prevalence of child porn on /b/ during a Q & A with users this week posted to 4chan:

Q: Moot, what is your stand on child porn?
A: Disgusting/highly illegal and I can't believe you people treat it as a joke.

All fun and games until someone gets five years in federal prison. [The Smoking Gun, 4chan (NSFW)]