David Clayton-Thomas, the iconic frontman of the band Blood, Sweat & Tears, has died at the age of 84. The Canadian singer began his career performing in prisons before joining the group in the 1960s. Blood, Sweat & Tears achieved significant success with Clayton-Thomas, winning two Grammy Awards and selling millions of records worldwide, including hits like "Spinning Wheel" and "You've Made Me So Very Happy" in the Netherlands. The band was a prominent act at the 1969 Woodstock festival and notably became the first rock group to perform behind the Iron Curtain in 1970. Clayton-Thomas left the band in 1972 for a solo career, later rejoining in the early 1980s. He was inducted into the Canadian Hall of Fame in 1996 and passed away in a Toronto hospital; the cause of death has not been disclosed.