Cho Doo-soon, one of South Korea's most notorious child predators in recent history, was released from prison on Saturday amid protests against the malevolent criminal's return to society.

Cho was 57 years old when he was convicted in 2009 of kidnapping, beating and raping an eight-year-old girl in a church bathroom in Ansan, near Seoul, in December 2008.  

The girl was left with permanent internal injuries, losing about 80 percent of her colon. She will need a colostomy bag for the rest of her life, according to court records.

Cho, who spent 12 years behind bars, will reportedly live in his old house in Ansan. 

Angry protests near his residence threw eggs at him and shouted slogans calling for his execution or expulsion from the city, Yonhap News Agency reported Saturday.

A bill proposing mandatory life sentences for child rapists has been introduced by lawmakers. But people dread the thought of a deadly criminal preying upon innocuous children. Even the fact that Cho will be tracked by a GPS device 24/7 has failed to clam frayed nerves.

The victim and her family moved a few weeks ago from their home which is about one kilometer (half a mile) away.

"Where Cho moved to is a residential neighborhood with a school and a kindergarten nearby," the victim's father said in an interview, adding "If Cho did look back on himself at least a little bit, it doesn't make sense that he would have decided to move in there."

Local police claimed they will monitor Cho around the clock and have "installed 15 new CCTV cameras" and "raised the brightness level of 30 street lamps" in the neighborhood.

(With input from agencies)