Details were not immediately available. The new government of Prime Minister Shinzo Abe came to power in December.
Japan's Justice Ministry said at the end of last year, 133 inmates were on death row, the highest number since 1949. There were no executions in 2011.
Kyodo said a total of nine people were hanged during the 39-month rule of the previous government. The last executions were in September 2012 when two death row inmates were hanged.
Japan is one of the 32 nations that have the death penalty. U.N. figures show about 150 nations have either abolished the death penalty or do not practice it.
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