Block request to uri

I need assistance with creating an iRule to drop requests which are sent to a specific uri. I understand that I could use the else statement to redirect to page which displays a 404 or something similar but in this case I simply want to drop the requests. How would I define the action "drop."

 

 

rule drop_admin {

 

when HTTP_REQUEST {

 

if { [HTTP::uri] starts_with "/admin"

 

} else {

 

 

Thank you in advance.