Alonzo Patrick Fox, 89, a retired Army lieutenant general who spent more than 40 years on active duty before retiring in 1959 as a special assistant to the secretary of Defense, died of cancer Dec. 15 at Sibley Memorial Hospital. He lived in McLean.

At the outbreak of World War II, he was promoted to brigadier general and in 1943 became assistant commander of the 102nd Infantry Division. He served with the division through campaigns in northern France, the Rhineland and central Europe.

In 1946, Gen. Fox joined the headquarters staff of General of the Army Douglas MacArthur as deputy chief of staff of the Supreme Command Allied Powers. Upon the outbreak of the Korean conflict and the formation of the United Nations command, he became deputy chief of staff of that organization. He participated in the Inchon, Korea, landings in September 1950.

The following year, Gen. Fox became the Army member of the Joint Strategic Survey Committee, a senior advisory group of the Joint Chiefs of Staff. From 1955 to 1957, he was military adviser to the assistant secretary of Defense for international security affairs. During those years, he accompanied American delegations to summit, disarmament and foreign ministers meetings.

Gen. Fox was a native of St. Louis and graduated from St. Louis University in 1917. He received an infantry commission later that year. His military decorations included the Distinguished Service Medal, the Silver Star Medal, the Legion of Merit, and three Bronze Star medals. He also received decorations from France, The Netherlands and the Soviet Union.

His wife of 36 years, the former Elizabeth Jordan, died in 1964. Survivors include a son, Army Col. Eugene A. Fox of Arlington; a daughter, Patricia Fox Haig, the wife of retired Army general Alexander M. Haig Jr., a former secretary of State, of McLean; a brother, Lawrence D. Fox of Tulsa; a sister, Genevieve Bolfing of St. Louis; five grandchildren, and two great-grandchildren.