His publicist, Mia Hansen, attributed his death to natural causes, the wire service said.
Reddick was often put in a suit or a crisp uniform during his career, playing tall, taciturn and elegant men of distinction, AP reported. He was best known for his role as Lt. Cedric Daniels on the HBO series "The Wire."
"The Wire" creator David Simon praised Reddick on Twitter: "Consummate professional, devoted collaborator, lovely and gentle man, loyal friend. Could go on, but no, I can't go on. This is gutting. And way, way, way too soon."