The Ministry of Justice said Monday it will devise measures to step up monitoring of convicts wearing electric ankle bracelets, following the incident over the weekend where a man, who had cut off his monitoring device and took off, turned himself in to police and said he killed two women.

The ministry said at a briefing it will make the device harder to cut off, enhance cooperation with police by swiftly sharing information on criminals wearing such a device and introduce an improved system to gauge the level of risk of recidivism.

The ministry has hardened the device over the years, but the incidents of a forcible removal of the device have repeatedly occurred. Eleven criminals have cut off the device as of July this year, and two were still on the loose.

It also said it will strengthen penalties for convicts who violate the law on electronic surveillance, an offense punishable by up to seven years in prison or 20 million won ($17,000) in fines, and add more personnel to monitor them.

According to the ministry there were 4,847 convicts on electronic monitoring devices as of July, which translates into 17.3 convicts per each officer assigned to monitor them.

Prime Minister Kim Boo-kyum issued a public apology regarding the harrowing crimes through social media, saying he feels a "heavy sense of responsibility" for not having been able to prevent the alleged murders beforehand.

He promised to review whether there were any problems during the initial response of the justice ministry and the police, and also pledged to improve the joint response system among law enforcement institutions during emergency situations to prevent similar crimes from occurring in the future.

On Sunday, Songpa Police Station arrested the 56-year-old man, surnamed Kang, for ripping off the ankle device and allegedly murdering two -- one before he ran off and the other while he was on the run.

The man turned himself over to police at around 8 a.m. Sunday, reportedly saying he feared being arrested soon for his crimes.

Police had been chasing him since Friday, when he ran away.

The police found the victims' bodies at the man's house and in his car. The two women, in their 40s and 50s, respectively, are said to have known the man.

The man was set free in May, wearing the electronic ankle monitor, after serving 15 years in prison over his 2005 conviction for robbery and sexual assault, crimes he committed only five months after his release from prison for similar crimes, according to the police.

The police said he had 14 previous convictions, mostly for robbery and sexual crimes. He was under supervision by the probation office as he was considered at high risk for recidivism. (Yonhap)