A Chinese teen was held captive in a man’s flat for six years – giving birth to children fathered by both the man and his son – until the girl’s mother found and rescued her, mainland media reported on Tuesday.

Her captor, a man surnamed Deng, fathered a boy now about four or five years old and has been charged with rape, the Shanghai-based news site Thepaper.cn, reported.

The man’s son – whose age was not disclosed – fathered a pair of boy-girl twins, now about one year old, the news outlet said.

It was not clear if the son faced criminal prosecution.

In 2012, when the girl was 14 years old, she left her home in Zhumadian, a city in central China’s Henan province, after a dispute with her brother over his refusal to give her money to use at an internet cafe. Her family never let police know that she was missing, the report said.

Her father had left the family years ago, according to the report. At the time, her mother, Li Ailing, had been serving a 2011 prison sentence for economic crimes.

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It was not until Li was released in July 2016 that she learned her daughter had been missing for four years.

Li started walking around the city and putting up missing-person posters in hopes of finding her daughter. In January she was in a residential area putting up a poster when a woman in shabby clothing smiled at her.

She said she immediately knew it was her daughter, according to Thepaper.cn.

Despite her mother’s repeated attempts to get her to recognise her, the daughter kept denying she knew who her questioner was. Li then cornered her and urged her to look closely at the face before her.

After a long while the young woman finally called Li “Mom” but refused to go home with her, mumbling the word “children”, according to the report.

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Li then called in police to intervene.

When Li and the police went to the flat where the daughter had been living, they found the three children.

After the daughter came home with Li, she showed signs of mental trauma. She struggled to talk to people and giggled when she was alone. She was later diagnosed with schizophrenia, a mental disorder that affects how a person thinks, feels and behaves.

Li managed to determine from the scattered information she got out of the daughter that the young woman, now 20 years old, had been abducted by Deng soon after leaving the family home in 2012, according to the report.

The man had kept her captive in his flat until she gave birth to the twins.

After numerous attempts to have the man’s family prosecuted for the abduction, the mother – who still did not know the exact circumstances that had led to her daughter’s pregnancies – eventually agreed to a settlement brokered by police in July that would have had Deng’s son marry the daughter.

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“Considering my daughter already had three children, I decided to give in and marry her to the family, until she told me the father undressed her, too,” Li was quoted as saying.

At the time, Li did not know the elder Deng and her daughter had had sex. But when the daughter told her mother that Deng had undressed her, the mother began to suspect her daughter’s oldest child had been fathered by Deng.

A DNA test she requested verified her suspicions. Police subsequently arrested Deng and charged him with rape.

Further genetic testing showed the twins had been fathered by Deng’s son.

“At first I could not understand how my daughter could become a schizophrenia patient within six years,” the mother was quoted as saying on Thepaper.cn.

“She was only 14 [at the time]. How could she handle this?” she said.

The daughter later said that after she had been taken to Deng’s flat she was undressed in the presence of Deng’s wife. She tried to leave but was beaten badly and was afraid to try to leave again. She was forced to sleep with the father and the son, she said.

The daughter has not seen the children since leaving the flat almost a year ago, according to the report. Her mother did not try to take them when she rescued her daughter and the children have remained with Deng.

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