A study by Japan's Diet has found that children as young as 9 years old were forcibly sterilized under the Eugenic Protection Law that was scrapped in 1996.

Officials of the Diet's research authorities handed a 1,400-page report to the heads of the Upper and Lower Houses on Monday.

Government data show that about 25,000 people underwent sterilization procedures due to disabilities and other reasons.

The study was conducted based on the 2019 law aimed at providing relief to the victims.

The law also stipulates that an investigation into how procedures were carried out to prevent similar cases from happening again.

The researchers looked into 6,550 cases whose records had been kept at local governments. They found that the youngest people involved were two 9-year-olds, a boy in the 1960s and a girl in the 1970s, who underwent surgeries that deprived them of reproductive abilities.

Some victims were sterilized at the request of family members or as a condition to enter welfare facilities. In other cases, people were deceived into believing that they would undergo surgeries to remove the appendix or receive treatment for anemia.

Upper House President Otsuji Hidehisa was the leader of a cross-party group that helped draft the 2019 law. He said each lawmaker has to take the report seriously so as not to repeat the tragedy.

The report is available on the websites for both chambers of the Diet.