Easy way to get them off of any website is to report what they traced or stole with links, images, and other proof. Like on DA it'll give you a "report deviation" option on every deviation.
Telling them to go away is harder, I've done it successfully before, but it is more frustrating, time consuming, and gives them enough time to alert their fans where they will go to leech more money off of them.
Some say any publicity is good publicity, so why would you want them to linger?
Report in secrecy and you won't have to deal with any of their fans backlashing at you.