Like including "Guccifer 2.0" the "hacker" that originally claimed responsibility for the DNC breach being outed as a Russian intel agent directly linked to the GRU or aside from that?
Anyone can claim responsibility, and moreover, being 'responsible' doesn't mean you had some capabilities. Such as with skiddies who employ a chinese DDOS botnet. The people responsible are the ones running the botnets and selling their useage, not the people trying to utilize this.