JAKARTA: Indonesia's president will soon sign a decree authorising the use of chemical castration to punish paedophiles, the attorney general said, following a string of headline-grabbing child sex crimes.

Indonesia will join a small group of nations that allows such punishment, including Poland, Russia, and Estonia, as well as some American states. In 2011, South Korea became the first Asian country to use chemical castration as a punishment.

"We are very concerned about child molestation abuse cases. This phenomenon has reached extraordinary levels," Attorney General H.M. Prasetyo told reporters after a cabinet meeting late on Tuesday.

"It has been agreed that there will be additional punishment in order to make people think a thousand times before doing this," he said.

President Joko Widodo is expected to issue a presidential decree soon approving the punishment after the cabinet agreed to the measure late on Tuesday, Prasetyo said.

Chemical castration would involve injecting convicted paedophiles with a female hormone in the hope “his sexual desire will vanish”, he said.

The rape last year of a 6-year-old student by a group of janitors at the United States-embassy backed Jakarta Intercultural School rekindled calls for tougher punishments.

There have been a number of other high-profile child sex crimes since then. A 9-year-old schoolgirl was raped and killed in the capital, Jakarta, earlier this month.

A 39-year-old man has been arrested in relation to that case. Police believe the girl was strangled with a cellphone charger cable, Indonesian media has reported.

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