A 54-year-old prisoner who confessed to a 1980 murder in a letter to police while he was serving a prison term for a separate crime was released from prison here on Saturday.
The man admitted murdering Yoshiki Koyama, a 21-year-old salaried worker from Nagano Prefecture, at a reservoir in the prefecture's village of Ikusaka.
In April 2000, the prisoner forwarded his confession to the Nagano Prefectural Police. At the time, he was serving a term of five years and four months, handed down by the Nagano District Court in May 1998, for violating the Stimulants Control Law.
On Monday, the police sent papers on the murder case to prosecutors. But the 15-year statute of limitations has already expired.
The police had initially ruled that Koyama's death was a suicide after his bound body had been found in the reservoir on March 29, 1980. They believed he had tied himself up as part of his plan to commit suicide.
But when the police questioned the prisoner, he provided information that could only have been known by the culprit. The police concluded that he had bound Koyama and thrown him into the reservoir on March 1, 1980.
On Thursday, the man met Koyama's 67-year-old mother, Hatsue, inside the Takamatsu prison. They spoke for more than two hours, during which time he apologized for murdering her son.