Japan's prisons had 129 inmates on death row as of Dec 26, according to a Justice Ministry report.
The ministry said that there were three executions in June and August, while five death-row inmates died of illnesses, including a 92-year-old man, TV Asahi reported Sunday.
A man believed to be the world’s longest-serving death row inmate, Iwao Hakamada, 78, was freed in March after the Shizuoka District Court ordered a fresh trial over the grisly 1966 murder of his boss and the man's family.
Human rights group Amnesty International has criticized Japan's use of capital punishment for being "shrouded in secrecy."
Japan and the United States are the only major industrialised democracies to carry out capital punishment, a practice that has led to repeated protests from European governments and human rights groups.
International advocacy groups say the Japanese system is cruel because death row inmates can wait for their executions for many years in solitary confinement and are only told of their impending death a few hours ahead of time.© Japan Today