A testy exchange between Donald Trump and Joe Biden in Thursday's TV debate has renewed focus on the unknown whereabouts of parents of 545 migrant children separated from their families under US border policy.
President Trump appealed to his right-wing base by defending the "zero-tolerance" policy that prosecuted immigrants who crossed into the US illegally, separating over 5,000 children from their parents in 2017 and 2018.
"The children are brought here by coyotes and lots of bad people, cartels, and they're brought here and they used to use them to get into our country," said Trump in the second and final TV debate before the November 3 election.
Biden retorted that the approach -- which failed to put in place a system to reunite the families, most of whom were fleeing poverty and violence in Mexico and Central America -- "violates every notion of who we are as a nation."
"Their kids were ripped from their arms and separated... now those kids are alone, nowhere to go, nowhere to go. It's criminal," said the Democratic nominee.
In June 2018, a judge ordered the government to reunite the separated families.
The task fell to activists and volunteer lawyers who travel through small towns in countries such as El Salvador add Honduras, put out radio adverts and speak to community leaders to try to find parents.
They are not always successful, however.
Trump said his government was trying to find the parents but that in the meantime the children are "so well taken care of" in facilities that are "so clean."
A lawsuit filed by the American Civil Liberties Union on Tuesday claimed that the parents of 545 children, about 60 of whom are under the age of five, separated when the policy began with a pilot program in Texas in 2017 are yet to be located.
"History will judge"
Lawyers estimate that roughly two-thirds of more than 1,000 parents separated from their children were deported.
Lee Gelernt, the ACLU attorney in charge of the lawsuit, said the separation was "the worst practice" he had seen in three decades of fighting for human rights.
"We HAVE to find them," he tweeted. "History will judge."
Krish O'Mara Vignarajah, president of the Lutheran Immigration and Refugee Service (LIRS), one of the organizations the government asked to help find the parents, said she was "shocked" by Trump's comments.
"If the president thinks Mylar blankets, concrete floors, windowless rooms and chain link fences are child welfare standards he's sorely mistaken," she told AFP.
Those conditions "were just the beginning of a three-year nightmare that has not ended and that will perhaps traumatize them for the rest of their lives," she added.
"They'll go to bed tonight as they have for a thousand nights not knowing where their parents are," said Vignarajah, recalling harrowing recordings and images of children crying at the border after being separated.
The task of reuniting the families is a difficult one, as the US government did not keep records on all parents separated from their children.
Many were deported to remote areas and do not have internet access, while some only speak indigenous languages and not Spanish.
George Hoffman, director of the Immigration Clinic at the University of Houston in Texas, said the failure resembled more than just inter-agency miscommunication.
"It's incredible negligence," he told AFP.
"Rolling out these policies that are meant to energize their base but without any legal authority. That's exactly what happened here," Hoffman added, also citing a travel ban on several Muslim-majority countries that was blocked by various courts.
"We made a mistake"
Trump has not fulfilled his 2016 electoral promise to build a wall with Mexico and has deported less than half of the three million undocumented immigrants he said he would expel from the country.
But he gave the immigration law enforcement agency known as ICE more powers to detain foreigners and imposed measures to discourage asylum applications, among other measures.
During the debate, Trump attacked Biden over the immigration policies of Barack Obama's administration when he was vice-president.
Obama deported 3.2 million between 2009 and 2016.
"Who built the cages, Joe?" Trump needled repeatedly, referring to photos in 2014 which showed migrants being temporarily housed behind chain-link enclosures.
The president asked why Biden was now promising a path to citizenship for undocumented migrants when Obama failed to achieve it during his eight years in power.
If elected, Biden says he will ask Congress to legalize America's 11 million illegal immigrants, including children who arrived with their parents, known as "dreamers."
"We made a mistake, it took too long to get it right," he said.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)