The Trump administration is warning illegal aliens to "turn back now" as President Trump ushers in his promised crackdown on mass immigration through the southern border.

Shortly after taking the oath of office on Monday, Trump signed a blitz of executive orders to immediately tighten immigration enforcement.

The 47th president declared a national emergency at the border and discarded his predecessor's "catch and release" policies, which enabled an influx of millions into the nation's interior.

"Turn back now"

The emergency declaration authorizes the military to assist with Trump's promised mass deportations of millions of aliens. Trump's order directs the military to "seal the borders and maintain the sovereignty, territorial integrity, and security of the United States by repelling forms of invasion including unlawful mass migration, narcotics trafficking, human smuggling and trafficking, and other criminal activities."

Trump's deputy chief of staff Stephen Miller, a veteran of his first administration and famous immigration hardliner, warned aliens to "turn back now."

“All illegal aliens seeking entry into the United States should turn back now. Anyone entering the United States without authorization faces prosecution and expulsion," Miller said.

Trump also ended the Biden administration's CBP One App, which allowed nearly 1 million immigrants to enter the U.S annually. The app's website now states the app is offline and all “existing appointments have been canceled.”

Trump's immigration reforms have been at the center of his political identity since he first ran for the presidency with a pledge to build a border wall between the U.S. and Mexico. While campaigning for re-election, Trump vowed to carry out the largest deportation operation in the nation's history.

The pace of Trump's new immigration crackdown is faster compared to his first term, and its scope is broader. Trump did not declare a national emergency at the border until more than halfway through his first term, in 2019, to divert Pentagon funding for the border wall after Congress refused to provide it.

Trump's crackdown begins

In his most drastic immigration action since reclaiming the presidency, Trump suspended birthright citizenship, which grants automatic citizenship to anyone born on U.S. soil. Critics of birthright citizenship say the policy gives illegal aliens a loophole to stay in the country through their U.S.-born children, known as "anchor babies."

Trump's order challenges the conventional wisdom that the 14th Amendment guarantees birthright citizenship. His move has already prompted lawsuits from 22 different Democratic states.

Trump also designated foreign criminal gangs as terrorist organizations and invoked a 1798 law, the Alien Enemies Act, to dismantle these groups where they operate on U.S. soil. The activities of these gangs were a highlight of Trump's re-election campaign, which drew attention to the seizure of apartment blocks in Colorado by the Venezuelan Tren de Aragua gang.

Trump also suspended the refugee resettlement program - which brought a large influx of poorly vetted Afghans into the country under Joe Biden - and ended the asylum process indefinitely until the "invasion" of the border is over.

Meanwhile, in a show of force, Immigration and Customs Enforcement (ICE) raids began in cities across the land on Tuesday.