|Born||June 6, 1890
Kagoshima Prefecture, Japan
|Died||January 21, 1948
|Allegiance||Empire of Japan|
|Service/branch||Imperial Japanese Navy|
|Years of service||1912-1945|
|Commands held||Cruiser Division 16|
|Battles/wars||World War II|
A native of Kagoshima Prefecture, Sakonju was a graduate of the 40th class of the Imperial Japanese Navy Academy in 1912, placing 98th in a class of 144. He served his midshipman tour on the cruiser Soya, and battleship Suwo, and after commissioning as an ensign was assigned to Hashidate.
After his promotion to lieutenant on 1 December 1919, he was assigned to the Tenryū, served a year as communications officer on Chichijima in the Ogasawara Islands, and returned to serve as communications officer on Mutsu, and seaplane tender Wakamiya. He was promoted to lieutenant commander in 1930, and was executive officer of the Kako in 1933. He held numerous staff positions thereafter, including that of naval attaché to Thailand from 1 September 1941.
He was promoted to rear admiral on 15 October 1941, and continued to remain in Thailand until June 1942.
He was assigned as commanding officer of the Cruiser Division 16 in September 1942, with the heavy cruiser Tone as his flagship. CruDiv16 played an important role during many naval battles of World War II.
In March 1944, CruDiv 16 was engaged in attacking Allied shipping sailing between Aden and Fremantle. The 6,100-ton British steamer MV Behar, crewed mostly by Indian seamen, was sunk about midway between Ceylon and Fremantle on 9 March 1944. Following this attack, the squadron broke off its mission and returned to Batavia, as it was feared that Allied ships responding to the Behar's distress signal posed an unacceptable risk. Tone took 114 survivors aboard, but was unable to land the prisoners at Batavia, as new orders had been received from Tokyo that no further prisoners were to be taken in combat operations other than those needed for interrogation. When Sakonju protested that the prisoners could not very well be kept aboard Tone for the duration of the war, he was advised that they should be "disposed of". Ten days later, Tone Captain Haruo Mayuzumi ordered the prisoners to line up on the aircraft deck. Apparently randomly, Mayuzumi selected 52–72 men (accounts vary), and ordered them shot on the fantail after they refused the honor of death by sword, and pitched the bodies into the Indian Ocean. Those killed included 10 of 14 officers on the MV Behar, and most of the Royal Navy crew.
In 1946, Sakonju was arrested by the American occupation authorities and extradited to Hong Kong, where he was charged with war crimes by a British military tribunal over his role in the murder of the survivors of the Behar. Sakonju took responsibility in his 1947 affidavit. "In view of the fact that the Allies are lately killing Japanese prisoners of war at Guadalcanal by running tanks over them and are often bombing and torpedoing Japanese hospital ships, causing many casualties, the H.Q. came to a conclusion that the Allies are aiming at the reduction of Japan's manpower, and H.Q. decided to retaliate." Sakonju was hanged in January 1948.
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