A Japanese court ruled Thursday that an 88-year-old former boxer was not guilty in a retrial for a 1966 quadruple murder, reversing an earlier decision that made him the world's longest-serving death row inmate.

In a retrial that began after he spent 45 years on death row, 88-year-old Iwao Hakamada was found not guilty of a 1966 quadruple homicide.

The world's longest-serving death row prisoner, Iwao Hakamada, was acquitted on Thursday, over 50 years after his murder conviction.