President Donald Trump has ordered immigration officials to begin deporting “millions” of illegals from major U.S. cities starting next week.

Trump made the announcement in a tweet on Monday night, saying U.S. immigration agents will begin mass arrests starting next week.

“Next week ICE will begin the process of removing the millions of illegal aliens who have illicitly found their way into the United States,” Trump tweeted. “They will be removed as fast as they come in.”

Trump said the lawbreakers will be removed from major U.S. cities around the country. Thousands of ICE agents have been recruited and trained to take part in the massive operation.

The massive arrests have been secretly planned for months, as thousands of illegal immigrants from as far away as Africa pour into the U.S. across the southern border.

According to Dispatch.com, “Large-scale ICE enforcement operations are typically kept secret to avoid tipping off targets.”

Immigration officials who were slow to act on the crisis at the border were removed from their positions.

In April, acting ICE director Ronald Vitiello and Homeland Security Secretary Kirstjen Nielsen were terminated after they expressed concerns about the massive plan to arrest illegals.

They were concerned that more children would be separated from their parents or guardians. Images of immigrant children crying inside cages sparked public outcry around the nation.

Former acting ICE director Vitielo was replaced by former FBI and Border Patrol official Mark Morgan, who has impressed Trump with his tough talk on immigration.

“We will be going after individuals who have gone through due process and who have received final orders of deportation,” said Morgan on June 4.

He said immigrants who failed to show up for their hearings will also be rounded up and deported.

That will include families,” he said, adding that ICE agents will treat the parents and children they arrest “with compassion and humanity.”

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