Two separate murder cases, in which a teenage girl and a woman fell victim to sex crimes, are shocking the nation, testifying to the need for more stern and effective measures to be taken to prevent such tragedies from happening again.

A 45-year-old man under police detention confessed to kidnapping and killing a 10-year-old girl, whose body was found Sunday one week after she went missing on her way to school in Tongyeong, South Gyeongsang Province.

Police arrested another 46-year-old man on Jeju Island on Monday for murdering a female tourist and dismembering her body.

The public shock was amplified by the suspects’ brazenness and cruelty. The man in Tongyeong behaved as if he had been the last witness of the girl, telling a TV reporter before his arrest that he had seen her before going to work in the field near his house.

Police said the Jeju murderer severed a wrist of the 40-year-old female tourist and left it with her shoes at a bus stop about 18 km from the crime scene to confuse the investigation.

Calling the two incidents extremely worrisome, President Lee Myung-bak instructed his aides Monday to come up with emergency measures to protect women and children from sex crimes.

Various methods such as public access to an Internet database of sex offenders, electronic anklets and chemical castration have already been used in the wake of a series of heinous sex crimes. But the recent murder cases show such efforts still remain far short of protecting women and children from sex offenders.

The man accused of murdering the 10-year-old girl was a convicted sex offender who served a jail term for attempting to rape a woman in 2005, revealing the laxity of government oversight.

Legal loopholes should be tightened and law enforcement officers should strengthen monitoring on likely sex offenders.

Currently, the child sex offender database is managed by the Gender Equality Ministry while the Justice Ministry runs a database of people convicted of sex offences against adults. It is desirable for the two databases to be merged into one probably under the management of the Justice Ministry.

Police are required to make more frequent and tighter monitoring of convicted sex offenders, especially those against minors. Strengthening monitoring is needed as convicted sex offenders are likely to commit another crime like the suspect in Tongyeong.

Though recently taking a tougher stance, the judiciary should try to get closer to the public sentiment of due justice in handling sex crimes. According to court figures, six out of 10 sex offenders were either fined or received suspended sentences in 2010.

In a 2011 survey by the Supreme Court, more than 58 percent of respondents agreed on the need to give prison sentences to sex offenders even if they settled with victims. It might have to be considered to introduce a system to issue arrest warrants for suspected sex offenders without exception to preempt a repetition of crimes, as practiced in some U.S. states.