"What happens in the case of a situation where the parents may be undocumented but the children are American citizens and going to school," Khanna said. "Is this administration going to again separate kids from their parents?"
Khanna said Congress should exercise "vigorous oversight" over ICE.
"We need to make sure that people's rights are being protected, we need to make sure that the agencies are complying with the law," he said. "We need to make sure that ICE is doing its primary function, for which Congress appropriated funds, and that is protecting against sex trafficking, drug trafficking, child trafficking, that is the primary threat that the United States faces at the border. It's not the people who are undocumented who are living here, paying taxes, working, who have kids going to school.
Oakland Mayor Libby Schaaf called Trump's policies, including the latest plan, "frightening" and "racist" during a press conference Tuesday. She said mass roundups can easily lead to civil rights violations.
"I cannot stomach this racist hate mongering from someone who is in government," said Schaaf.
Schaaf said it is ironic that Trump would make such an announcement about potential raids when she had once been criticized by the president for warning Oakland residents about similar operations in her city.
Schaaf said Oakland will remain "unapologetically" a sanctuary city, "We are not breaking any laws. We are simply not using our precious local resources to in any way assist with what is a federal civil matter and that is immigration enforcement."
Peter Jon Shuler and Marnette Federis contributed to this report.