The star of "The Andy Griffith Show" and "Matlock" was buried on his family farm hours after he died Tuesday morning. He was 86.
E! News said his death certificate reported the actor suffered a heart attack 24 hours before he died. He had a history of coronary artery disease, hypertension and hyperlipidemia, a condition related to high cholesterol, the report said.
Celebrity Families of 2014 [PHOTOS]