A Japanese court sentenced a former U.S. base worker to life in prison Friday for the rape and murder of a 20-year-old woman in Okinawa in April last year, saying the crime leaves "no room for leniency."

The Naha District Court handed down the sentence on Kenneth Franklin Shinzato, 33, in line with prosecutors' demand. The defendant had admitted to the charges of rape resulting in death and abandoning the victim's body but denied intent to murder.

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"His criminal responsibility is grave," the court said in its ruling, adding the crime was conducted with "selfish motivation, which left no room for leniency."

The case sparked public anger and strengthened anti-U.S. base sentiment in Okinawa, which hosts the bulk of U.S. military facilities in Japan and has seen a series of crimes committed by U.S. servicemen or military-linked personnel.

According to the indictment, Shinzato attacked the woman for the purpose of raping her on a road in Uruma in central Okinawa around 10 p.m. on April 28, 2016. He stabbed her in the neck with a knife and struck her on the head with a bar so she would not resist, killing her as a result.

The remains of the woman, who was taking a walk at the time of the crime, were found on May 19 that year in a wooded area in the village of Onna, north of Uruma. They were found based on information in Shinzato's statement.

Shinzato said in his last statement during the trial, "I did not intend to cause such a result."

He was a civilian working for an internet company within the premises of the U.S. Kadena Air Base in Okinawa at the time of the incident, after serving as a U.S. Marine from 2007 to 2014, according to his lawyers and the U.S. Defense Department.

He was a civilian working for an internet company on the premises of the U.S. Kadena Air Base in Okinawa at the time of the incident, after serving as a U.S. Marine from 2007 to 2014, according to his lawyers and the U.S. Defense Department.