This is not a new threat or spam but is new to Mac but is very easy to remove or ignore (on a Mac). I say ignore because it is just spam that makes it hard to exit because they launch 150 copies of the page.
NOTE: DO NOT PAY since this will not stop the threat. It’s just SPAM.
To exit this on Safari simply click on the menu bar and click reset Safari but there is also a better solution below.
In System Preference’s you can set “Close windows when quitting applications“. Then you simply need to quit Safari and when you reopen it the ransom-ware site will be gone.
You can read more on this threat at this website:
For years, Windows users have been plagued by ransomware demanding several hundred dollars to unlock their computers.
It is much more complicated and requires reboot and booting in safe mode to remove on a PC. It can also be a real threat since it can even encrypt your files (windows only). There is too many steps to list here but you can read how at this site: