The Chichijima incident (also known as the Ogasawara incident) occurred in late 1944, when Japanese soldiers killed and consumed five American airmen on Chichi Jima, in the Bonin Islands.
Nine airmen escaped from the planes after being shot down during bombing raids on Chichi Jima, a tiny island 700 miles (1,100 km) south of Tokyo, in September 1944. Out of the nine airmen eight soldiers were captured by Japanese. George H. W. Bush(41st President of the United States from 1989 to 1993) was the only one to evade capture by the Japanese. He was picked up by the U.S. Navy after a few hours in a life raft in open water. After the war it was discovered that the captured airmen had been beaten and tortured before being executed. The airmen were beheaded on the orders of Lt Gen. Yoshio Tachiban. American authorities claimed that Japanese officers then ate parts of the bodies of four of the men.
Tachibana, alongside 11 other Japanese personnel, was tried in August 1946 in relation to the execution of U.S. Navy airmen, and the cannibalism of at least one of them, during August 1944. Because military and international law did not specifically deal with cannibalism, they were tried for murder and “prevention of honorable burial”.
This case was investigated in 1947 in a war crimes trial, and of 30 Japanese soldiers prosecuted, five (Maj. Matoba, Gen. Tachibana, Adm. Mori, Capt. Yoshii, and Dr. Teraki) were found guilty. Tachibana was sentenced to death, and hanged. In his book Flyboys: A True Story of Courage, James Bradley details several instances of cannibalism of World War II Allied prisoners by their Japanese captors. The author claims that this included not only ritual cannibalization of the livers of freshly killed prisoners, but also the cannibalization-for-sustenance of living prisoners over the course of several days, amputating limbs only as needed to keep the meat fresh.
Source: Chichijima Incident