Ana Escobar was held at gunpoint in her shop while her baby was stolen
DNA tests in Guatemala have proven for the first time that a child put up for adoption through the state system was stolen from her mother, officials say.
Ana Escobar reported her daughter Esther Sulamita stolen last year and during her search saw the baby with a US woman who was adopting her.
The baby had a false birth certificate but DNA tests proved the parentage and Esther is now back with Ms Escobar.
Baby thefts have long been suspected and Guatemala froze adoptions in May.
Guatemala is second only to China as the source of babies adopted by US parents and the adoption process is worth tens of millions of dollars a year.
Last year, more than 4,700 Guatemalan children were adopted by Americans.
Dozens of Guatemalan mothers have reported stolen babies.
Ana Escobar said armed men had locked her in a storage closet at the family's shoe shop north of Guatemala City and abducted six-month-old Esther in March last year.
Ms Escobar spoke to the BBC last November, saying the authorities had closed the case but that she would not give up the search.
"I'm 100% sure that we will find my daughter," she said at the time.
Ms Escobar took part in protests with other mothers, including wheeling empty prams in front of government buildings to call for justice.
Ms Escobar searched hospitals and orphanages and while at the National Adoption Council's offices in May saw a toddler she was convinced was Esther.
Jaime Tecu, director of a team of experts reviewing all pending Guatemalan adoptions, said: "She was so sure that the child was hers that we agreed to search the house where the baby was kept."
A Guatemalan judge allowed Ms Escobar to care for Esther while the new DNA tests were performed.
Ms Escobar told Associated Press news agency on Wednesday: "I can't explain how excited and happy I am. It's a miracle."
Mr Tecu said: "This is the first time that we've been able to show, with irrefutable evidence, that a stolen child was put up for adoption."
He said officials would investigate the lawyers who handled the adoption, the doctor who signed earlier, falsified DNA tests and anyone else associated with the process.
"This was run by a mafia, and we are going after them," he said.
BBC Americas correspondent Warren Bull says hundreds of children were being bought or stolen to order each year because Guatemala's adoption system had been so quick and trouble-free for would-be parents.
The Guatemalan congress tightened laws on adoption in December to try to prevent abuse of the system.
In May the authorities suspended the adoption of some 2,300 children by foreigners and are reviewing each case to check if the babies were genuinely being offered for adoption by their birth mothers.