The head of Immigration and Customs Enforcement said efforts to deport families with orders to leave the country will continue after an upcoming national sweep that President Trump said would start Sunday.

Matthew Albence, the agency's acting director, said targets were on an "accelerated docket" of immigration court cases for predominantly Central Americans who recently arrived at the U.S. border in unprecedented numbers. Similar operations occurred in 2016 under former President Barack Obama and in 2017 under Mr. Trump.

"This family operation is nothing new," Albence told The Associated Press. "It's part of our day-to-day operations. We're trying to surge some additional resources to deal with this glut of cases that came out of the accelerated docket, but after this operation is over, these cases are still going to be viable cases that we'll be out there investigating and pursuing."

Get Breaking News Delivered to Your Inbox

The operation will target people with final deportation orders on 10 major court dockets, including Chicago, Los Angeles, New York and Miami. Albence said that doesn't mean arrests will be limited to certain areas. Authorities will go where their investigations lead, even if it's five states away from where the case is filed.

Mr. Trump said authorities were "focused on criminals as much as we can before we do anything else."

"It starts on Sunday and they're going to take people out and they're going to bring them back to their countries or they're going to take criminals out, put them in prison, or put them in prison in the countries they came from."

The operation further inflamed the political debate over immigration as Mr. Trump appeals to his base with a pledge to crack down on migrants and Democrats cast the president and his administration as inhumane for going after families.

The Obama-era family operation in 2016 resulted in about 10% of those targeted being arrested, and the 2017 effort had a lower arrest rate, Albence said. Other operations that have targeted people with criminal arrest records have yielded arrests rates of about 30%, aided by access to law enforcement databases.

"If you have an individual that's been arrested for a criminal violation, you're going to have much more of an investigative footprint," Albence said.

Administration officials have said they are targeting about 2,000 people, which would yield about 200 arrests based on previous crackdowns. Mr. Trump has said on Twitter that his agents plan to arrest millions of immigrants in the country illegally.

It is highly unusual to announce an enforcement sting before it begins. The president postponed the effort once before after a phone call with House Speaker Nancy Pelosi, but immigration officials said it was also due in part to law enforcement concerns over officer safety because details had leaked.

But they're pressing ahead with this one, even though the president and other administration officials have discussed the long-planned family operation for months.

"Nothing to be secret about," Mr. Trump said. "If the word gets out, it gets out because hundreds of people know about it."

The operation will target entire families that have been ordered removed, but some family may be separated if some members are in the country legally. Albence gave a hypothetical example of a father and child in the U.S. illegally but a mother who isn't

"If the mother wants to return voluntarily on her own with the family, she'll have an opportunity to do so," he said.

Families may be temporarily housed in hotels until they can be transferred to a detention center or deported. Marriott said it would not allow ICE to use its hotels for holding immigrants.

If ICE runs out of space, it may be forced to separate some family members, Albence said. The government has limited space in its family detention centers in Texas and Pennsylvania.

"If hotels or other places do not want to allow us to utilize that, it's almost forcing us into a situation where we're going to have to take one of the parents and put them in custody and separate them from the rest of their families," he said.

Meanwhile, activists ramped up efforts to prepare by circulating information about hotlines and planning public demonstrations. Vigils outside of detention centers and hundreds of other locations nationwide were set for Friday evening, to be followed by protests Saturday in Miami and Chicago.

The impending raids come amid controversy over migrant detention facilities at the border. Democrats argue that overcrowding at these facilities lead to inhumane conditions intensified by hardline Republican policies, while Republicans blame the conditions on Democrats' unwillingness to approve stricter immigration laws.

The House Oversight and Reform Committee held a hearing on the treatment of migrants at the southern border Friday, after Democrats on the committee released a report of poor conditions in detention centers.

Rep. Alexandria Ocasio-Cortez gave passionate testimony about her visit to a border facility, saying that "the cruelty (at the border) is manufactured" by hard line immigration policies ordered by the president.

"When these women tell me that they were put into a cell and that their sink was not working, and we tested the sink ourselves, and the sink was not working. And they were told to drink out of a toilet bowl. I believe them. I believe these women," she said.

"We are not getting the accounts of migrants, of their treatment, of what they're experiencing," Ocasio-Cortez continued. Her voice breaking, Ocasio-Cortez said that the worst part of her visit was that "there were American flags hanging all over these facilities."