Like the Shakas, Pahlavas, Kambojas, Paradas, a section of the Rishikas had also migrated to west/south-west India prior to Christian era.
But the Udyoga-Parva of Mahabharata groups the Pahlavas with the Sakas, Paradas and the Kambojas-Rishikas and locates them all in/around Anupa region in western India.