Brazen blackmail: "Your site and your site information has been hacked by a group of hackers"

Hello, your site and the information of your site has been cracked by a group of hackers until we take any action, but if you do not accept our conditions we are supposed to take our measures, you should understand the seriousness of this situation ... my advice is to preserve the credibility of your company ... our conditions Only $ 20,000. Your answer is waiting for 3 days after you receive this letter, time will go ... do not try to track us, use fake passwords and mail!

Here is a letter with the signature "Seryoga Mikalin (mikalin [] bk.ru)" was received today by the editors of one of my projects (link removed. And then any mention of the project is now perceived as PR). Spelling and punctuation of the author saved.

Has anyone else gotten something like this?