By Tom Mustin

GOLDEN, Colo. (CBS4) – The Jefferson County District Attorney’s Office is sending out a warning to parents about secret Facebook groups that pose a risk to children.

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The groups go by names like “Only if UR High.” They’re private groups on Facebook, selling illegal drugs to children.

(credit: CBS)

(credit: CBS)

“I’ve seen acid, mushrooms. I’ve seen everything on there,” an 18-year-old high school student named “Brian” told CBS4’s Tom Mustin.

The Jefferson County District Attorney’s Office’s Child Sex Offender Internet Investigations Unit, or Cheezo, recently shut down a hidden Facebook group called Fly Society 420 after the mother of a 15-year-old girl blew the whistle. The page advertised everything from pot to prescription drugs to LSD.

Mike Harris heads the Cheezo unit. He showed Mustin the site. Items such as marijuana and OxyContin were all sold all on a hidden page.

CBS4's Tom Mustin interviews Mike Harris (credit: CBS)

CBS4’s Tom Mustin interviews Mike Harris (credit: CBS)

Of the 900 secret followers, 170 Denver metro area students were traced to the page — some as young as 13. Parents can’t track the site unless they’re logged onto Facebook in their child’s name.

“Parents need to know. The general public needs to know. These things are out there and it’s very concerning.” Harris told Mustin.

Brian says he has bought and sold drugs on a Facebook group. He says the groups are locked to keep parents away. Members have to be invited to the group. When one disappears, several others take its place.

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(credit: CBS)

(credit: CBS)

“Anyone can make a page. It’s that easy. You tell your friends and they tell their friends.”

He showed Mustin some new Facebook groups that have already popped up — all through word of mouth. Brian admits the pages can be a haven for predators.

“It’s dangerous. People post on the website. Don’t trust this person. He robbed me.”

As for closing the sites, he says parents hold the key.

(credit: CBS)

(credit: CBS)

“There’s not much you can do but check up on your child’s Facebook.”

“Does your mom check up on you?” asked Mustin.

“No,” he replied.

More information and tips for parents are available on the Jefferson County District Attorney’s Office’s webiste.

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Tom Mustin is CBS4’s Weekend Anchor. He has been with CBS4 since 2002, and is always looking for great story ideas. Connect with Tom on Facebook or follow him on Twitter @TomCBS4.