SAN FRANCISCO — The Trump administration said Friday it will begin arresting parents and other relatives who hire smugglers to bring their children into the U.S., a move that sent a shudder through immigrant communities nationwide.



The new "surge initiative" by Immigration and Customs Enforcement marks the latest get-tough approach to immigration by the federal government since President Donald Trump took office. The government says the effort aims to break up human smuggling operations, including arresting people who pay coyotes to get children across the U.S. border.



That marks a sharp departure from policies in place under President Barack Obama's administration, during which time tens of thousands of young people fleeing spiraling gang and drug violence in Honduras, Guatemala and El Salvador crossed the border. The children are then placed with "sponsors" — typically parents, close relatives or family friends — who care for the minors while they attend school and their cases go through the immigration court system.



The government now says it plans to arrest the sponsors.



"ICE aims to disrupt and dismantle end-to-end the illicit pathways used by transnational criminal organizations and human smuggling facilitators," agency spokeswoman Sarah Rodriguez said. "The sponsors who have placed children directly into harm's way by entrusting them to violent criminal organizations will be held accountable."



Officials did not respond to questions Friday seeking details on the number of sponsors who would be targeted or already had been arrested, or what charges would be applied. Immigrant advocacy groups said they were investigating a dozen arrests or ongoing investigations in Texas, Pennsylvania, New York and Virginia.



Elsy Segovia, an immigration attorney in Newark, New Jersey, said armed agents visited her client on Wednesday under the guise of checking something with his Social Security number, then announced he was being investigated for smuggling his 16-year-old nephew from El Salvador, who crossed the border in Arizona last week.



"They coerced him into giving over his phone, and they said if you don't tell the truth, we will take away your temporary protected status," Segovia said, referring to a program that has allowed many Salvadorans to legally live in the U.S. "He is very, very worried."



The man's nephew had been fleeing gang violence in El Salvador, and the agents told him they knew he had wired money to smugglers coyotes to get his relative to the U.S., Segovia said.



Department of Homeland Security spokeswoman Gillian Christensen said that as a matter of policy, the agency could not comment on an ongoing law enforcement action.



"Arresting those who come forward to sponsor unaccompanied children during their immigration proceedings, often parents, is unimaginably cruel," said Wendy Young, president of Kids in Need of Defense, a nonprofit that has matched thousands of unaccompanied minors with attorneys in the last eight years. "Without caregivers to come forward, many of these children will languish in costly detention centers or be placed in foster care at great expense to states."



Immigration enforcement was a centerpiece of Trump's presidential run, and he has sought to carry through on his campaign promises by cracking down on people in the country illegally. He has vowed to build a wall on the U.S-Mexico border and go after "sanctuary cities" that enact favorable policies toward immigrants, while emboldening ICE to arrest more people.



At the Annunciation House shelter in El Paso, at the westernmost point of Texas' border with Mexico, director Ruben Garcia said more families are beginning to arrive after a big decline in numbers in recent months. The Trump administration had sought to take credit for that decline, saying its policies and Trump's signature promise to build a U.S.-Mexico border wall were keeping people away.



"To zero on you smuggled so and so and so you contributed $3,000 to the cartels, and to try to isolate the discussion that way, is pretty disingenuous," Garcia said. "If we really cared anything about the impact of some of these policies and some of these practices, then we would be much more engaged in how do we solve this."



Children whose sponsors were arrested would be placed with another verified relative or guardian, or under the care of the Office of Refugee Resettlement, the federal agency that takes custody of unaccompanied minors, Rodriguez said.



Since October 2013, nearly 170,000 unaccompanied minors have been placed with sponsors in all 50 states and the U.S. Virgin Islands, and many are still awaiting their day in court, according to federal data. ICE officials said they were intervening after three incidents in Texas in recent years in which unaccompanied minors had been injured, sexually assaulted or locked into tractor trailers.



Last year, an Associated Press investigation and a bipartisan congressional probe found that the agency's own inadequate screening had endangered more than two dozen migrant youth in the government's care, including six Guatemalan minors who were placed with traffickers and forced to work on egg farms. The office later made numerous internal changes to strengthen its safeguards, but the program again came under fire recently after some unaccompanied minors were recruited by gangs in the U.S.



Leon Fresco, a former Obama administration Justice Department official, said Trump's recent move likely would be challenged in court, given limits on the amount of time children can be detained.



"This sends a signal to young people who would cross the border not to cross, or your relatives will be placed in removal proceedings," said Fresco. "This is a policy change to say a minor is no longer to be treated as a person worthy of our sympathy, but instead to be treated as another unlawful entrant whose entrance must deterred at all costs."