An academic has found a copy of an official U.S. military document detailing the procedures to be followed at the 1948 execution of seven Japanese convicted as Class-A war criminals by the International Military Tribunal for the Far East.

The original four-page document, titled "Execution of Prisoners," is kept at the U.S. National Archives and Records Administration. Kenji Nagata, a Kansai University associate professor studying the death penalty, said he found photocopies at the National Diet Library in Tokyo.

It is the first time a comprehensive official record covering the full scope of the Dec. 23, 1948, executions of the seven men, including wartime Prime Minister Gen. Hideki Tojo, has been found.