SAN FRANCISCO — On Monday morning Facebook launched Marketplace on iOS and Android so its 1.7 billion users could buy and sell stuff to each other right inside the Facebook mobile app. Within hours, Facebook users were selling stuff that Facebook says they can't.

Drugs. Animals. Adult services. Weapons. Themselves. Even body parts (and by body parts we mean crotch shots that would make Anthony Weiner blush.)

All of which is pretty much the A to Z of stuff that violates Facebook's commerce policy.

When asked if it was worried about people selling stuff they shouldn't, Facebook told USA TODAY last week that it would take "appropriate action to make Marketplace a safe place for people."

Translation: Facebook would rely on users to report posts that violate Facebook's policy so that Facebook could review them.

"We actually have a commerce policy that covers all of Facebook, and not just Marketplace, that lays out what products are OK and what products are not," Marketplace product manager Bowen Pan said. "On top of that we also give a lot of tools to our community to directly report and flag products that violate our commerce policies."

According to Business Insider, Facebook says it will also now have employees tracking down posts that violate its policies.

Some Facebook users are just having a bit of fun, such as the ad for six ounces of water for $56 (bottle not included).

Here are some of people's favorites from Twitter. Or Mic has a collection of verboten items for sale on Facebook Marketplace.