WASHINGTON – President Donald Trump confirmed Friday that border agents will begin raids in selected American cities this weekend to remove people who are in the United States illegally.

"It starts on Sunday and they're going to take people out and they're going to bring them back to their countries," Trump told reporters at the White House.

"We are focused on criminals as much as we can before we do anything else," he said.

Trump's opponents have urged him to hold off on the raids, calling them an unnecessary overreaction and arguing that they are likely to ensnare innocent people, including migrants who missed court dates they didn't know they had.

"Every person in America has rights," said House Speaker Nancy Pelosi, D-Calif. "These families are hard-working members of our communities and our country. This brutal action will terrorize children and tear families apart."

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The raids are expected to target ten yet-to-be-disclosed cities.

Trump discussed the raid as Vice President Mike Pence visited the southern border to tour a migrant detention facility in Texas. House Democrats, meanwhile, held hearings on what observers have described as poor living conditions at those facilities.

Promoting Pence's trip, Trump defended the detention facilities by saying "they are crowded because we have a lot of people. But they're in good shape."

Speaking at the White House before a trip to Milwaukee and Cleveland, Trump talked about the raids even as administration officials have complained about leaks regarding their plans.

"There's nothing to be secret about," Trump said. "ICE is a law enforcement. They are great patriots. They have a tough job ... If the word gets out, it gets out because hundreds of people know about it. It's a major operation. So if the word gets out, it gets out."

Matthew Bourke, a spokesman for U.S. Immigration and Customs Enforcement, has said the agency would not discuss details of the operations, “due to law-enforcement sensitivities and the safety and security of U.S. Immigration and Customs Enforcement personnel."

Contributing: Alan Gomez