Three child rapists were executed on Wednesday after their death sentences were approved by China's top court, showing the country's "zero tolerance" against those harming juveniles.

The behaviors of the three criminals, who had sexually assaulted and raped girls for a long time or several times, greatly damaged the physical and mental health of the minors and seriously challenged the legal and moral bottom line, bringing extremely negative effects to society, the Supreme People's Court said.

In one case, a former primary school teacher surnamed Guo was found to have raped six girls, who were all less than 14 years old, more than 100 times from 2013 to February 2019 and molested three others under the age of 12 multiple times.

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Another rapist surnamed Shang, from 2011 to 2020, lured eight young girls at bus stations, in parks, or around kindergartens at first and then took them to hidden places to sexually abuse them.

During the period, Shang secretly took videos and photos of the sexual assault and of the private parts of the victims to force them to maintain long-term relationships with him. By pressuring them, he continued to rape four of the victims for a long time, and one of them fell into severe depression and anxiety.

The third rapist was a farmer surnamed Gong, who ran a small shop in a village. He was discovered to have seduced and mentally controlled a young girl of the same village for a long period when she came to the shop to play and then sexually assaulted her either alone or with other people.

From summer 2015 to January 2020, Gong raped the girl eight times alone and gang-raped her twice, and also molested her alone or jointly more than 40 times, which caused the victim to slit her wrists and take pesticides to kill herself at the age of 16.

The convictions and death sentences given by lower courts to the three rapists should be approved, as they seriously violated the teachers' ethics, brought severe mental anguish to the children and even resulted in one of the victim's death, the top court said.

It emphasized the importance of juvenile protection, reaffirming the judicial efforts to fight against people who harm children.

It revealed that the crime of sexual assault of minors has been increasing over the past few years, adding that criminals in more than 90 percent of such crimes were people close to the children, including relatives, neighbors and teachers.

Left-behind children in rural areas and children with mental problems were more likely to become the criminals' targets of sexual assault, it said, noting that the victims have become younger, with those under the age of 14 accounting for a higher proportion.

Hotels, rental apartments, bars, karaoke rooms and bath centers were common places of sexual assault, and many criminals raped and sexually abused children after luring them on the internet, it added.

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"Chinese courts have always attached importance to juvenile protection, with ‘zero tolerance' and harsh punishment against those harming children," the top court said in a statement.

While deterring criminals with the death penalty, it also called on juveniles to enhance their awareness and ability of self-protection, learning to seek helps from families, schools and public security departments if suffering from difficulties.

Additionally, parents and teachers should provide stronger law, safety and sex education for children, it said, urging more walks of life, such as cyberspace administrations and government agencies to join the team of children protection.