Lord Infamous, one of the founding members of Three 6 Mafia, died Friday in Memphis. He was 40. The cause of death is still unknown, although he did suffer a stroke and a heart attack in 2010. Born Ricky Dunigan, Lord Infamous began his rap career with Three 6 Mafia, then known as the Backyard Posse. Along with his family member Paul, the group eventually included rappers Koopsta Knicca, Crunchy Black and Gangsta Boo, and became known as one of the notorious hip-hop crews in Memphis.