Blocking referal urls with .htaccess?

Anyone know if there is a way to block referals from other sites.

Someone signed my site up for one of those adsense click groups where people click eachothers ads and I want to know if I can block everyone coming from that domain.

 

RewriteEngine on
RewriteCond %{HTTP_REFERER} (domainyouwanttoblock\.com) [NC,OR]
RewriteRule .* - [F]

Code (markup):

That should do it for ya

 

Thanks exam, I'll give it a go.

 

I've tryed this code but all I get is an internal 500 error. I know rewrite is enabled because I use it on other things, any other suggestion?

 

Ok, I finally got it working. This is what I used if anyone else has the same problem.

RewriteCond %{HTTP_REFERER} ^http://www.blockeddomain.com [NC]
RewriteRule .* - [F,L]

Code (markup):

I had to enter the code twice to block the domain with and without the www prefix. So my final code looked like this:

Thanks