"Please stop posting photos of your children visible to anyone on Facebook and elsewhere!" the police warned.
"Children have a private life too!"
The police advice is specifically targeted at parents posting "snapshots from the beach or [children] swimming naked in the paddling pool."
They warn that "maybe you find these photos cute today, but your child will think they're hugely embarrassing in a few years. Bullies might even use them against your child.
"And worse: people with paedophilic tendencies make use of these photos for their own purposes and might publish them somewhere else."
"Photos of children don't belong on social media. The internet 'forgets' nothing," they conclude.
Inevitably, the post whipped up a storm of comment and reaction after being shared almost 90,000 times on Facebook.
"I'm really shocked by the recklessness of some parents, but also by the fact that there's apparently nothing at all that can't be abused," one person wrote.
"I can't understand why everyone posts their children online. My partner and I decided not to post any photos of our child on the internet while I was still pregnant, and we asked our friends not to put any photos they took online," said another.
Others thought that the police reaction was out of proportion.
"Don't be annoyed with me, dear police, but then the paedophiles will just go to the beach or to the swimming pool," one person commented. "There are better photos to be had there than online."
Another wrote that the post was "totally exaggerated."
"Children are a part of society, why should they be censored on Facebook?" she wrote. "That's just like when women are censored in Arabia because otherwise they could arouse sexual desire. What nonsense!"
But it has run into trouble in Germany for its failure to enforce those rules, with Facebook founder and CEO Mark Zuckerberg promising Chancellor Angela Merkel to do more to fight racist hate speech at a recent meeting.