Anderson Cooper 360

Sign language interpreter tries to explain his actions at Mandela memorial

He had the eyes of the world upon him as he stood just feet from some of the world's most powerful leaders. The man who apparently spent hours signing gibberish during Nelson Mandela's memorial claims he's schizophrenic and was hallucinating at the time. CNN's David McKenzie spoke with the sign language interpreter and Robyn Curnow has the latest on the controversy.