The Yumiko-chan incident refers to the rape and murder of a six-year-old girl named Yumiko Nagayama (sometimes reported as Yumiko Arakaki) by a 31-year-old American soldier stationed in Okinawa, that took place September 3, 1955, ten years into the U.S. occupation of Okinawa, which at that time was not part of Japan. Yumiko went to kindergarten that day. It was noticed at about 8 p.m that she was missing, when she didn't come home from playing outdoors when the sun set.
The next day, her body was found in a military garbage dump on the Kadena Air Base. She had been raped and murdered, and her body looked as if it had "been cut up with a sharp knife from the abdominal region to the bowel.” An indictment was submitted against Sergeant Isaac J. Hurt (sometimes incorrectly reported as Isaac J. Hart) of B Battalion, 32nd Artillery Division, on charges of murder, rape and kidnapping of a girl. 
Anger against the U.S. Military occupation of Okinawa was stirred up due to the horror of the incident, and the fact that due to extraterritoriality laws foisted upon Okinawa by U.S. forces, the alleged rapist/murderer would not face Okinawan justice, but rather a U.S. military court martial. From the end of the Battle of Okinawa in 1945 until 1972, Okinawa was governed by the United States Civil Administration of the Ryukyu Islands.
A Rally for Protection of Children was held in Okinawa and the Association for Protection of Children was formed with this incident, and massive numbers of Okinawans rallied in support of the cause. Okinawans demanded that the U.S. military "Punish offenders of this kind of case with the death penalty without leniency regardless of nationality or ethnicity." Okinawans demanded that he be tried in a civilian court and that the trial be broadcast—requests that were ignored.
Isaac J. Hurt was brought up on charges of rape and murder by a U.S. court-martial in Okinawa. His court martial lasted 13 days, during which time he insisted upon his innocence. He was convicted after a deliberation of less than an hour. His was the second conviction for rape of a U.S. serviceman on Okinawa in less than a month. However, his case was later appealed. He was returned to the U.S. and not executed.
The incident led to further debate over the continued presence of U.S. forces in Japan, and was the springboard for the first serious, coordinated anti-U.S. military protests in Okinawa following the beginning of the occupation.
- Rape during the occupation of Japan
- Sexual assault in the U.S. military
- 1945 Cave of the Negroes incident
- 1995 Okinawa rape incident
- 2002 Okinawa Michael Brown incident
- The Okinawa Times, Sept 10, 1955.
- The Okinawa Times, Sept 10, 1955
- St. Petersburg Times, December 6, 1955