Mechon world

The Mechon worlds were planet where Mechanoids were planted by humans. On one such world, Mechanus, the Daleks came into conflict with the Mechanoids. As there were a number of other worlds where the Mechons waited for humans, the Daleks knew that there would be serious problems should the Mechanoids be allowed to grow in strength. Accordingly, they began to systematically search out and destroy all of the Mechon worlds in what was known as the Mechon Wars. (PROSE: The History of the Daleks)