Synagogue of Satan comes to mind. There were a number of claims in the late 80s and 90s of secret tunnels underneath schools and similar, where children would be taken to participate in Satanic rituals. Of course, whenever the police arrived to investigate, the tunnels were filled in or similar and any evidence was explained away. I think the devil worshippers got better ownership of media since then, and such stories dried up.
My understanding is that the "Jews" who attended this synogogue were quite high up in terms of wealth and status in society. I would not be surprised to find these were involved in similar Satanic rituals and/or slave trading (human trafficking). What is surprising (or maybe not really) is how shy the media has been to report on the subject. If it were a Catholic priest molesting kids, it would be plastered all over the news (and rightly so). Sad that it seems because these criminals claim to be "Jews", they are given a different legal standing.