The detention of a mother in Nanjing, Jiangsu province, who is alleged to have physically abused her 9-year-old adopted son, has aroused public concern over the corporal punishment of children by parents, and about amendments to the Child Protection Law.

On Sunday, the Nanjing police announced that the adoptive mother, a relative surnamed Li, had been detained on abuse charges.

On Friday, pictures of the boy showing bloodstains on his back, feet and hands went viral on the Internet. A schoolteacher uploaded the pictures to draw public attention to his plight and to call for the punishment of those responsible.

"One of the boy's teachers discovered that he had received more injuries recently. And he showed personality changes, preferring to be alone," the schoolteacher said online.

According to the posting, the boy said that his adoptive mother had beaten him with water pipes and branches, burned him with water vapor, jabbed him with pointed objects, whipped him with ropes, struck him with a scratching rod and trampled on his feet - all for failing to finish extra homework she had given him.

According to the local police, the boy was adopted at age 6. Both adoptive parents, one a lawyer and the other a reporter, have good educational backgrounds.

The boy was taken to the home of his biological parents in Chuzhou, in neighboring Anhui province.

Zhang Chun, director of the Psychological Crisis Intervention Center in Nanjing, said that psychologists will visit the boy and provide professional counseling.

"The government and experts must be very cautious before taking the boy away from his adoptive parents," said Zhang. "It's possible that he thinks he will be abandoned for a second time."

Under a regulation that took effect on Jan 1, parental custody can be revoked if the rights of minors are infringed, including sexual assault, physical abuse leading to severe mental or physical damage or refusing to perform the duties of a guardian.

According to the Beijing Youth Legal Assistance Research Center, from 2008 to 2013, about 75 percent of the 697 child abuse cases exposed by media were committed by parents.

Zhang said that the traditional Chinese concept holding that it is a natural right of parents to beat their own children also contributes to child abuse.

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