Robert F. Wagner, a U.S. senator's son who was mayor of New York from 1954 to 1965 and later U.S. ambassador to Spain, died Tuesday, apparently of natural causes. He was 80.

Police and an ambulance crew were called to Wagner's Manhattan home early Tuesday, said Capt. Michael O'Loughlin of Emergency Medical Services. Wagner was pronounced dead at the scene.Wagner, a lifelong Democrat like his father, had a political career that included tenure as a state assemblyman, Manhattan borough president and U.S. envoy to the Vatican.