If you have a few IPs sending 10s of hundreds of visits. It's highly likely, they are trying to DDoS you.

You can block them with .htaccess or iptables

http://www.htaccesstools.com/block-ips/

https://serverpilot.io/community/articles/how-to-block-ip-addresses-with-htaccess.html

https://www.ip2location.com/blockvisitorsbycountry.aspx

https://www.cyberciti.biz/faq/how-do-i-block-an-ip-on-my-linux-server/

FraudFilter can't block these IPs, you must block them at your server to prevent them from exhausting your server resources.

If you are not using our recommended setup, then please ask your hosting provider to block the list of IPs.