Banning IP's that aren't numerical

[CFN-1]

There are several bots from china and russia that sit on my site 24/7, sucking bandwidth. I've tried banning them as they appear in the "Who's On" screen, but it doesn't seem to affect them.

Here's one:

spider80.yandex.ru

How do I ban users with this type of "IP" address?

I've tried the email banning also. It also didn't work.

I'd like to ban any address that originates in china or russia.

I run a Florida Tourist site. I don't need Chinese and Russian bots.

Thanks for any help!