A woman has been arrested on suspicion of selling her seven-year-old son to strangers for £4,000.
The mother-of-three, 36, advertised her boy as being for sale to pay off her debts, it has been alleged.
Named only as Nargiza, she has since been detained under Russia ’s child trafficking laws.
Volunteers from the anti-slavery charity Alternativa posed as purchasers, responding to the woman’s advertisement.
Nargiza is then accused of meeting the “buyers” in the food court of a shopping mall in Yekaterinburg, east of the Ural Mountains.
She brought the boy with her and said he “didn’t mind” being traded to a new family, it is claimed.
The sting operation to save the boy comes amid concern in Russia over children being traded into sexual slavery or for body parts with the involvement of organised criminal gangs.
“Until the end, we hoped it was a made-up story, that this was someone's stupid joke or a fraud for money,” a spokesman claimed.
“However, when our group, together with the employees of the organised crime investigation group, left for the 'deal', we witnessed the boy being sold. Nargiza received the money and gave the child to a person she did not know.”
The mother was detained and her son was placed in medical care.
“Nargiza explained that her husband did not like her eldest son, and they decided to sell the child to pay off their debts,” they added.
The family lived in a two-room apartment and were building their own house with an income of £1,650 a month.
The boy she allegedly attempted to sell was from a previous partner, but she has a younger boy and girl with her current husband.
Oleg Melnikov, of the charity Alternativa, earlier warned of a rise in Russian women selling their children compared to previous years.
He said the women often blamed financial difficulties but “low moral standards” also accounted for their actions.
“We know these kids have no chance to get legal documents. They will end up in the hands of beggars on the streets or paedophiles," he said.
Fears have been expressed that children can also be traded by sex criminals or for body parts.
Children in Russia are often found in the worst forms of child labour, including working on the streets and in commercial sexual exploitation.
