They also called on Trump to end family separations through the policy of prosecuting undocumented migrants.
Detained immigrant children have frequently been caught up in the enforcement side of that bargain.
The Bush and Obama administrations did use prosecutions against some adult illegal immigrants to fight back against surges of illegal immigration.
Trump later posted a tweet calling out Democrats again for the law, arguing that it's up to them to end the policy and reform other problems in the immigration system.
From January 2014 to April 2015, 60 percent of unaccompanied children from El Salvador, Guatemala and Honduras were released to a parent, about a third were released to other relatives, 8 percent to family friends and less than 1 percent was released to unrelated sponsors, according to a 2018 Government Accountability Office report.
Though the photos were meant to slam Trump's immigration policies at least one was published by The Arizona Republic in 2014 during the Obama administration.
In a detailed explainer, The Washington Post said it was unclear why the controversy, which has always been reported on, had suddenly gained traction on social media over the past few days. One particularly disturbing image showed two children sleeping on mattresses on the floor inside what appeared to be a cage.
The president's daughter tweeted a photograph of herself cuddling her 2-year-old son, as other Twitter users grappled with a Trump administration policy separating migrant children from their parents at the border - and reports that US authorities had lost track of almost 1,500 children seeking asylum. The caption refers to USA efforts to process 47,000 unaccompanied children at the Nogales center and another one in Brownsville, Texas.More news: Xiaomi Mi 8 launched: Specs, Price, Features, Release Date, and more
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Favreau said Tuesday he later deleted the tweet after social media users pointed out that the photos were taken during the Obama administration.
Trump used the opportunity to point to his solution to mass illegal immigration.
The Trump administration on Tuesday sought to blame Democrats for what it calls a "border crisis", claiming that Democrats were standing in the way of much-needed laws. Halsey criticised the timing of the 36-year-old First Daughter's Twitter photo with her youngest child amid reports that the US Department of Heath and Human Services had lost track of up to 1,500 migrant children in the United States. The law came amid concerns about border control officials and their treatment of children. Under previous policy, immigrant children were usually allowed to stay with their parents.
"We do place children here with people or parents who are here illegally", the official continued. HHS - that's the Department of Health and Human Services. When the refugee office made calls last to determine the whereabouts of 7,635 children placed with sponsors a year ago, they learned that 6,075 children were still with their sponsors, 52 had relocated to live with a nonsponsor, 28 had run away, and five "had been removed from the United States". Detainees sleep and watch television in a holding cell at the Nogales Placement Center on June 18, 2014.
"If you are smuggling a child, then we will prosecute you and that child will be separated from you as required by law", he said, adding: "If you don't like that, then don't smuggle children over our border".
In the same Saturday tweet, Trump also escalated his rhetoric on immigration in a way that is likely to further inflame the political atmosphere that will make any resolution of the issue even more elusive. "It was not an Obama policy". Going back to the presidency of George W. Bush, this policy was created to offer noncriminal immigrants a way to earn temporary status in the USA while awaiting a ruling on whether they would be granted asylum. It was not a Clinton policy. The Democrats gave us that law and they don't want to do anything about it.
However, Gelernt said that the Trump administration has made the decision to go through with a "systematic" and "unprecedented" separation of children and parents in an effort to deter families from crossing the border. But he later issued a corrected tweet: "These bad pictures are from 2014 when the government's challenge was reconnecting unaccompanied minors".
Sessions earlier in May announced the new rule, which sees parents who arrive in the USA illegally with their children sent to federal jail, while their young ones are kept in Department of Health and Human Services (HHS) shelters, warning: "If you are smuggling a child, then we will prosecute you and that child will be separated from you as required by law".