The administration of President Donald Trump will increase criminal prosecutions of parents entering the United States illegally and place their children in protective custody as part of efforts to tighten immigration enforcement, according to a Department of Homeland Security (DHS) official.
The policy, which the official said was signed on Friday, formalizes plans that have been under discussion for more than a year.
Reuters first reported the government's idea to separate parents and children apprehended at the border in March 2017.
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A month later, the administration said it was no longer considering the policy because of a drop in apprehensions of families at the U.S. southern border with Mexico.
Shortly after Trump took office, pledging a hard line against illegal immigration, border arrests fell. Apprehensions, however, are again on the rise and reaching levels seen during the administration of former President Barack Obama, frustrating Trump.
"Illegal immigration must end!" he tweeted on Friday.
Under the new policy, parents caught crossing the border illegally will both be separated from their children and criminally prosecuted.
"Those apprehended will be sent directly to federal court under the custody of the U.S. Marshals Service, and their children will be transferred to the custody of Health and Human Services' Office of Refugee Resettlement," the DHS official said in an email.
Families seeking asylum should turn themselves into authorities so their petitions can be processed instead of attempting to cross illegally, the official added.
Currently, border crossers are often deported after their apprehension without being charged criminally.
Immigration advocates say that family separations for criminal prosecutions and other circumstances have already been happening for months. The American Civil Liberties Union filed a lawsuit in February to challenge the practice.
In April, Attorney General Jeff Sessions announced a "zero tolerance" policy for prosecutions of all illegal entry into the United States, and cases have already begun ticking up. The DHS said that there have been about 30,000 prosecution referrals since the start of the 2018 fiscal year in October, up from 18,642 prosecutions for the entire 2017 fiscal year.
In prepared remarks released to the media at an event in Arizona on Monday, Sessions said the government would also go after immigrants who pay smugglers to bring children across the border.
"If you are smuggling a child, then we will prosecute you and that child will be separated from you as required by law," the remarks said. Sessions is expected to further discuss border enforcement in a Monday afternoon appearance in San Diego.