Now 45, the woman was the victim of human trafficking at just 13 years old, police said.

Bolivian officers had been gathering evidence on the woman's whereabouts for several months at the behest of their Argentine counterparts, before localizing her in a small town in the south of the country.

Once Bolivian authorities gave the authorization, police liberated the woman and her son.

The pair were transferred to Mar del Plata, her home town some 400 kilometers (250 miles) to the south of Buenos Aires, where she was reunited with family, Argentine police said.