A man who was a minor when he killed four people was among two death row inmates Japan executed Tuesday morning, the Justice Ministry said, in a rare move that highlights the sensitive debate on punishment of juveniles in serious criminal cases.

Teruhiko Seki, 44, was 19 at the time of the crime. He became the second inmate to be hanged for a crime committed as a minor and the first such execution in 20 years. Norio Nagayama, who also killed four people when he was 19, was executed in 1997.

Seki killed a 42-year-old corporate executive, the man's wife, 36, their 4-year-old daughter and the executive's 83-year-old mother, while injuring the only survivor, a daughter who was 15, in 1992. He also stole ¥340,000 ($3,000) from their house in Ichikawa, Chiba Prefecture.