WASHINGTON >> A hearing on Tuesday at immigration court in Van Nuys, California, was supposed to be routine for a young family from Colombia, the first step in what they hoped would be a successful bid for asylum.

To their surprise, the judge informed the father, Andres Roballo, that the government wished to dismiss his deportation case. Taken aback, Roballo hesitated, then responded: “As long as I stay with my family.”

Moments later, as they exited the courtroom into a waiting area, Roballo was encircled by plainclothes federal agents who ushered him into a side room. Other agents guided his shaken wife, Luisa Bernal, and their toddler toward the elevator.

Outside the courthouse, Bernal collapsed on a bench. “They have him, they have him,” she wailed. “We didn’t understand this would happen.”

Roballo’s arrest was part of an aggressive new initiative by Immigration and Customs Enforcement to detain migrants at immigration courts, the latest escalation by the Trump administration in its all-out effort to ramp up deportations.

Agents have begun arresting migrants immediately after their hearings if they have been ordered deported or their cases have been dismissed, a move that enables their swift removal, according to immigration lawyers and internal documents obtained by The New York Times.

The operations, which have taken place across the country in the past two weeks, have required a high level of coordination between the government lawyers in the courtrooms and the ICE officers waiting to make the arrests, according to the documents.

The tactic is a significant break from past practice, when immigration officials largely steered clear of courthouse arrests out of concern that they would deter people from complying with orders. Critics, including some former Homeland Security officials, say the practice is deceptive and could backfire.

“Arresting people there subverts the legal process and will make others too scared to show up in the future, ultimately pushing people further into the shadows and out of legal status,” said Deborah Fleischaker, a senior ICE official during the Biden administration.

“We don’t actually have an immigration process if we make it impossible for people to comply and move through the system as ours was designed,” she said. “People showing up for their immigration court hearings are by definition complying.”

Federal officials say the initiative saves valuable resources, allowing ICE to more quickly identify migrants who are subject to deportation rather than deploying officers to try to track down people after they leave court and often slip out of view.

“If an individual is going through proceedings and he’s going to take a deportation order, then and there we want to make the arrest of that individual,” Garrett J. Ripa, a senior ICE official in Miami, said in an interview.

“It’s easier on us,” he added, noting that the approach also avoided arrests in communities.

When asked whether the arrests could deter people from showing up to court, Ripa said it was not clear.

“I think it’s really just in the initiative stage,” he said. “So I don’t have any concrete evidence to show one way or the other.”

A senior ICE official said in a statement that the agency’s prosecutors still had discretion to dismiss cases.

Tricia McLaughlin, a spokesperson for the Department of Homeland Security, added that most migrants who illegally entered the United States in the past two years were subject to expedited removals.

“Biden ignored this legal fact and chose to release millions of illegal aliens, including violent criminals, into the country with a notice to appear before an immigration judge,” she said in a statement. “ICE is now following the law and placing these illegal aliens in expedited removal, as they always should have been.”

The migrants being targeted in court are typically there because the federal government has initiated deportation proceedings against them for their illegal entry into the United States, not for other alleged crimes. A number of them may also be seeking asylum as a defense to deportation because they fear returning to their countries.

Greg Chen, a senior director at the American Immigration Lawyers Association, said his organization had documented dozens of arrests in courthouses across 11 states and 16 cities in the past two weeks. Those detained have included migrants whose statuses have not been resolved by the courts or who have opposed efforts to dismiss their cases, lawyers said.

“We are concerned that this is a form of collusion between the courts and ICE,” Chen said. “Many are eligible for asylum or other legal protections, but because the Trump administration is pressuring judges in courtrooms to dismiss the cases so that ICE can arrest and fast-track their deportation, it is depriving them of a fair hearing.”

A spokesperson for the Executive Office for Immigration Review, the agency in the Justice Department that runs the immigration courts system, declined to comment.

In New York on Wednesday, ICE officers wearing face masks and carrying photographs of migrants they were seeking to arrest waited by the elevators of the courthouses in lower Manhattan. Outside, protesters tried to block vans carrying detained migrants, leading to the arrests of 23 people.

Among the migrants arrested in a Manhattan courthouse lobby was a young Venezuelan man who appeared to be the first public school student in New York City to be detained by ICE since President Donald Trump returned to office. The student, a 20-year-old named Dylan, entered the country last year by registering through a mobile app the Biden administration had offered migrants to temporarily live and work in the United States while they applied for asylum.

When he showed up for a May 21 court date, his case was dismissed. He was followed into the elevator by ICE officers, who then arrested him in the lobby, according to his mother, Raiza.

“It was like a trap,” said Raiza, who spoke on the condition that her last name be withheld.

Dylan’s arrest followed the new playbook.

The day before, on May 20, ICE had circulated an internal memo instructing government prosecutors to help deportation officers with the operation, according to a copy obtained by the Times. The agency was seeking to arrest people who were either likely to be ordered deported or “amenable” to a fast-track deportation process known as expedited removal, the memo said.

Expedited removal, which does not require a hearing before a judge, was a process previously reserved for migrants picked up within 100 miles of the border. The Trump administration has expanded it to apply to migrants who have been in the country for fewer than two years.

If a migrant in the country illegally no longer has a case pending before the court, they can be subject to expedited removal. Under the new policy, ICE is encouraging prosecutors to look for cases that could be dismissed, which could accelerate deportations of more people, according to the internal guidance.