South Korea will expand chemical castration to include those convicted of sex crimes against minors under 19 and retroactively apply the law on disclosing personal information of sex offenders, the Prime Minister's Office (PMO) said Thursday.

The measure follows growing calls for tougher punishment against sex offenders and stronger preventive measures, including the medical treatment program in the wake of a recent string of such violent crimes victimizing women and children.

Under current law, those convicted of sex crimes against minors aged under 16 are subject to chemical castration. The new measure expands the age limit by three years to put more under the enforced hormonal treatment, according to the PMO.

The government also decided to retroactively apply the law of disclosing personal information of convicted sex offenders against minors.

Currently, the punishment was applied to those found guilty of sex crimes after the policy was introduced in 2011, but the government agreed to expand the period retroactive to three years earlier, the PMO said.

As part of efforts to increase support for victims of violent crimes, the government decided to set aside 1.03 billion won ($913,120) for victims' medical treatment and to establish shelters in six additional major cities, including Busan and Daegu.

Currently, such a center is only in operation in Seoul.

"The agreed measures will be discussed in the National Assembly to revise relevant laws, and we expect such measures to take effect next year," a PMO official said.

"Despite the government's countermeasures against violent crimes, we continue to see hideous crimes," PMO Minister Yim Jong-ryong said. "Ministries concerned are required to strive to put those measures into practice in close cooperation among different agencies to prevent and eradicate crimes."

Meanwhile, prosecutors in the southern city of Naju said Thursday they will seek court approval to force a 23-year-old rape suspect to go through the hormonal treatment and wear electronic anklets once released as part of any sentence he receives. The suspect, known only as Ko, stunned the nation earlier this month when he allegedly kidnapped and brutally raped a 7-year-old girl in his neighborhood.

The girl suffered a ruptured rectum and other serious injuries, sparking a public outcry for tougher punishments for sex offenders and causing President Lee Myung-bak to make an apology to the public for his government's inability to stop such crimes. (Yonhap News)