Retired Air Force Col. Thomas Arthur Fleek Sr., 61, an associate professor of forensic science and criminology at the University of the District of Columbia, died Sunday at Fairfax Hospital after a heart attack.

Col. Fleek was a combat veteran of World War II who later held high security and law enforcement posts in the Air Force. His assignments included duty stations in this country and abroad. He retired in March 1971.

He then joined UDC to help develop its Criminal Justice Department. He was the department chairman from 1972 to 1979. At the time of his death, he was an associate professor of forensic science and ciriminology.

Col. Fleek was a native of Nebraska. He joined the old Army Air Force during World War II and was a bombardier in B24 (Liberator) bombers in the Far East. He retired with the rank of major in 1946 to work as a journalist in Denver and Los Angeles. He rejoined the services in April 1951. He served in Korea, Japan, and the Philippines.

In 1957, he became chief of the management section of the plans and analysis group at Air Force Headquarters. In 1961, he was named director of security and law enforcement for the 5th Air Force in Japan. He later served as director of security police for the Pacific Air Command at Hickam Air Force Base appointed chief of the law enforcement and security division at Air Force Headquarters. He held this post until retiring from active duty.

He was a graduate of the University of the Philippines, the Armed Forces Staff College and the Air War College. He had done graduate work in international relations at George Washington University.

His decorations included the Mertorious Service Medal.

His marriage to Hilda Fleek ended in divorce.

Survivors include his wife, Lean A. Fleek of McLean; four children by his first marriage, Sheila Marie Tye of Corbin, Ky., Air Force 2nd Lt. Diana Lee Fleek Yeager of Choctaw, Okla., Thomas A. Jr., of Alexandria, and Kenneth Charles Fleek of Midwest City, Okla.; two sisters, Hazel Sutko and Glennis Koza, both of Phoenix; two half-brothers, Glenn and Calvin Olafson, both of Silver Creek, Neb., and four grandchildren.