There are thousands of murder cases that have been ordered on the internet. In forums, marketplaces, etc. This is very common. Cases that have been documented and tried with thousands of evidence.

Of course, most of these offers are scam. People trying to deceive others. But this is everywhere. The point is that a murderer is not able to kill thousands of people on demand. usually someone who wants to offer these services kills no more than 5 people. In general, people ask for someone with some proximity. An ex-security guard, a known ex-police officer, etc. When this possibility does not exist, He will search on the internet.

What does not exist are specific murder marketplaces that are reliable. Obviously, successful isolated cases may have occurred. But most of these marketplaces are scams. The big problem to be solved is the question of the oracle. In a negotiation between two parties, if one decides to deceive the other, we need a third party to decide who is right.

There are thousands of projects on track to offer this oracle without human interference. A decentralized oracle. It is an opportunity, but also a great risk.

https://www.wired.co.uk/article/kill-list-dark-web-hitmen