French police have found at least five babies apparently sold by a Bulgarian smuggling ring, and arrested the French couples alleged to have bought them.
French police found the children in traveller camps
The infants, all aged around 18 months, were discovered in traveller camps in Paris and some other parts of France.
They were allegedly bought by French couples for up to 6,000 euros (£4,000).
The couples face charges of kidnapping, incitement to child abandonment, falsification of birth certificates and human smuggling.
French police sources say the investigation began when a mother in Bulgaria alerted the police there, possibly after taking part in the scheme and then being overcome with remorse.
The joint inquiry with Bulgarian authorities lasted more than a year.
French authorities said they found a network run by a Bulgarian family that would find pregnant young women from poor families in Bulgaria and offer them between 400 and 1,000 euros to give birth in France and then hand over their baby to a French couple.
The women were also sometimes forced into prostitution in France.
A French children's court judge must now decide whether the babies should be returned to their adoptive parents or placed in foster care.