(CNN) The White House has told ICE officials to conduct dozens more workplace enforcement operations this year, a senior immigration official with knowledge of the conversations told CNN.

The news comes on the same day that President Donald Trump said raids like those in Mississippi this week are a "very good deterrent" for undocumented immigrants.

Shortly after the raids in Mississippi that led to the detention of at least 680 undocumented immigrants , US Immigrations and Customs Enforcement field offices across the country were instructed to identify at least two locations in their regions as potential targets for workplace enforcement operations, the source said.

Those operations can include criminal investigations, business audits and raids.

This week's raids led to a series of heart wrenching images and videos of family members -- including young children whose parents were detained -- reeling from the arrest of their relatives.

Trump on Friday defended ICE's workforce enforcement strategy as well as the agency's strategy for dealing with the children whose parents were detained.

Asked Friday why there wasn't a better plan in place to deal with the children after their parents' arrests, Trump told reporters outside the White House south lawn, "You have to go in, you can't let anybody know."

"Otherwise when you get there, nobody will be there," Trump said. "The big factor is to let people outside of the country that want to come in legally," he continued.

"I want people to know that if they come into the United States illegally, they're getting out," he said. "They're going to be brought out. And this serves as a very good deterrent."

"When people see what they saw (earlier this week), like they will be for a long time, they know that they're not staying," he added.

White House spokesman Judd Deere said it "does not direct law enforcement operations from ICE ... or any federal law enforcement organization."

At least 680 undocumented immigrants were detained during Wednesday's raids on seven meat processing plants in six Mississippi cities. More than 300 of them had been released by Thursday, Bryan Cox, an ICE spokesman, said in a statement.

US Attorney for the Southern District of Mississippi Mike Hurst told reporters that the raids are "believed to be the largest single-state immigration enforcement operation in our nation's history."

Earlier this summer, Trump tweeted that ICE would "begin the process of removing the millions of illegal aliens who have illicitly found their way into the United States." The operations were delayed

Other states appear to be attempting to prevent ICE from collecting employment data.

Last week, ICE requested direct access to the New Mexico Department of Workforce Solutions Department data. The request was denied on Friday based on concerns of privacy and civil rights. The secretary of the New Mexico Department of Workforce Solutions Bill McCamley said his department would consider data requests "for the purposes of investigating specifically identifiable criminal conduct on a case by case basis."

And Texas' Mexican American Legislative Caucus is launching an investigation into how much access ICE has to Texas employment records, Texas State Rep. Mary Gonzalez, vice chair for the caucus, said.