Washington(CNN) Sen. Kamala Harris on Monday said the Trump administration's new regulation that makes it easier to reject green card and visa applications is part of an ongoing effort by President Donald Trump to "vilify" immigrants.

The Trump administration's new regulation, paired with last week's enforcement raids, attempts to limit legal immigration and crack down on illegal immigration. Under the regulation, any green card and visa applicants could be turned down if they have low incomes or little education, and have used benefits such as most forms of Medicaid food stamps and housing vouchers, because they'd be deemed more likely to need government assistance in the future.

The move could dramatically cut the number of legal immigrants allowed to enter and stay in the US.

Harris told CNN's Kyung Lah it is a part of an "ongoing campaign of his to vilify a whole group of people."

The California Democrat, who was wrapping up a campaign swing in Iowa, accused Trump of "criminalizing" innocent people. Harris said on CNN's "Newsroom" that Trump is "ignorant" about the history of America -- "who we are, how we were founded and what are values are."

Harris, who was attorney general of California and sits on the Senate Committee on Homeland Security and Governmental Affairs, urged the President to put the "limited" resources "where they need to be."

The senator said Trump aims to distract the American public with having a "grand display" by sending the US military to the southern border and building a border wall, "which will never get built," she said.

"He wants everyone to be distracted from the fact that he has betrayed so many people and has actually done very little that has been productive in the best interest of American families," Harris said.

The senator said in last week's enforcement raids on food processing plants in Mississippi, "almost half of the people that they detained had to be let go because the policy was indiscriminate." She said children were detained and child protective services was not contacted, calling it "inhumane."

Immigration authorities detained some 680 undocumented immigrants in a massive sweep at seven Mississippi food processing plants in what a federal prosecutor described as a record-setting operation.