DNA tests on blood samples is slowly helping Argentines learn the fate of 30,000 people who went missing during the nation's brutal military dictatorship.
Victoria Schwindt is one grieving relative hoping to lay the ghosts of the past to rest and find her brother last seen in 1976 when he was 28 years old.
"I had a very hard time making a decision. I didn't sleep yesterday. Now it's done," said an emotional Schwindt, 65, as she held out an arm for a nurse to take a blood sample.
She hopes the DNA tests will help authorities locate her brother's remains.
"I'm sure he would have done the same for me," added Schwindt, as the nurse placed a cotton bandage on her arm.
On a white envelope next to her, read the words guiding the mission: "Your blood can help identify your loved one."
Out of the 30,000 people that rights groups say disappeared in Argentina during the 1976-1983 military dictatorship, only 350 have been identified since democracy was restored 27 years ago.
Nearly half of them were identified over the past three years, thanks to the national campaign launched in 2007 backed by massive government aid.
The campaign is taking place amid an escalating power struggle between President Cristina Kirchner and Ernestina Herrera de Noble, owner of the privately-held media group Clarin.
Noble adopted two children in 1976 suspected of being the son and daughter of a couple disappeared by the military regime.
When Kirchner recently called for the identification efforts to be stepped up, critics saw the move as fresh pressure on Noble, whose children refuse to have their DNA tested to see if it matches any of the missing.
But for thousands of others, the campaign represents a strong chance of realizing their long-held hope to find out what happened to their loved ones.
"These people come here with all their worries and unanswered questions," explained Nora Etchenique, who heads a blood therapy center in La Plata.
This city of 500,000 residents some 60 kilometers (37 miles) southeast of Buenos Aires was brutally repressed during the dictatorship.
"We must learn how to listen to them," she said. Etchenique was herself detained at a secret site near Buenos Aires known as the Sere Mansion, where her companion disappeared.
"It's up to the state, which stole the identity of all these people, to return it to them," she added.
Alejandra Toledo, a 43-year-old assistant at the center, was attentive toward Schwindt. She explained the samples will be sent to a lab in the United States, which will then cross-examine the data with all the information stored so far.
"In the beginning, we had 13 cases per day. I was in tears by the end of the day," she said. "Today, we have between three and four."
At the heart of the effort is an Argentine team of forensic anthropologists which has recovered 1,000 bodies.
"The government has put 63 hospitals at our disposal," said the team's co-founder Luis Fonderbrider as he scoured the room where the bones are stored.
"This allowed us to identify 120 people in the past two years, a considerable increase," Fonderbrider said.
In July, Frenchman Eric Domergue said thanks to the blood samples and the DNA tests he had recovered the remains of his lost brother, Yves.
They also helped Horacio Pietragalla, 34, discover that officials from the military dictatorship had stolen him as a child. And he found the remains of his true parents.
"The day I buried my mom, it was a moment of incredible happiness," he said at a cemetery in the Buenos Aires suburb of Lomas de Zamora.
"To be able to come here, leave a flower on her tomb, it's very comforting."