A girl with cerebral palsy whose body was found in a river in Nanjing, Jiangsu province, was pushed in by her father and grandfather, according to local police.
The 9-year-old was found dead with two bricks weighing a total of 4 kilograms in her red ladybug-shaped backpack on June 25.
Police in Nanjing's Jiangning district confirmed on its website that the girl had drowned, and they offered a 2,000 yuan ($295) reward to anyone who could provide information to identify the body.
However, no one claimed the body for a month after police released detailed information and posted many notices around the area. Police even increased the reward to 20,000 yuan.
The girl's father, surnamed Yang, 36, was detained by police at a construction site in Jiangning on Wednesday, together with the 65-year-old grandfather.
They confessed that they pushed the girl into the river to get rid of her on June 23, the police said.
A man surnamed Zhang, who was identified as the grandfather's son-in-law and worked as a house painter at the construction site, said the girl was the only child of her mother, who lives in Wuhu, in neighboring Anhui province, according to a middle-aged neighbor, Ma Qiang, who lives near Zhang. Ma relayed questions from China Daily to Zhang.
"Her family had collapsed because of her disease," Ma said Zhang told him. "Her parents, though not rich, spent about 100,000 yuan and took her to many cities for treatment."
"Her mother decided to give up on her and divorced the father when she was 3 years old," Ma continued. "Nobody in the family except the grandmother wanted the girl. She took the girl back to her hometown in Huaian, Jiangsu, to take care of her."
Ma said that Zhang told him the grandmother had taken care of the girl for six years. The grandmother returned to Wuhu for surgery, not long before the girl was taken to Nanjing by the father on the pretext of visiting the grandfather, who worked as a gatekeeper at the construction site.
When contacted by China Daily, a construction worker surnamed Liu said the grandfather stayed apart from the other workers and seldom communicated with them.
"Nobody working with him knew he had a granddaughter," Liu said. "He seldom smiled and kept things to himself."
Police are investigating the girl's death and said more information will be released to the public later.