Question about rejecting email

[David Jourard]

Hi,

I have mailscanner running for a while and haven't work with it for awhile.

Today a customer asked me to reject email for his email address coming from
email that ends in somename at somedomain.xx  where xx is a particular county
he is getting a lot of spam.

Could someone guide me on how to create a ruleset for this request.

Thank-you
David J.