The Trump administration has issued tough guidelines to widen the net for deporting illegal immigrants from the US, and speed up their removal.
Undocumented immigrants with a criminal record will be targeted first, along with those deemed a risk to US security or who have abused the benefit system.
All 11 million or so undocumented foreigners in the US could be affected.
But the plan leaves in place Obama-era protections for immigrants who entered the US illegally as children.
The Department of Homeland Security (DHS) plans to hire an extra 10,000 officers to implement the new measures.
"With extremely limited exceptions, DHS will not exempt classes or categories of removal aliens from potential enforcement," the department said.
"All of those in violation of the immigration laws may be subject to enforcement proceedings, up to and including removal from the United States."
The two memos released on Tuesday by the agency also call for authorities to prosecute parents who help smuggle their children into the country.
Some of the new priorities include:
- Expanding deportations to undocumented immigrants who have been charged with a crime, abused public benefits, misrepresented themselves or pose a risk to public safety - effectively allowing agents to arrest any illegal immigrant they encounter
- End US policy to release those caught on the border and instead place them into detention centres until their cases are resolved
- Allow planning to begin on an expansion of the border wall along the US southern border
Homeland Security Secretary John Kelly wrote in one of the memos: "The surge of illegal immigration at the southern border has overwhelmed federal agencies and resources and has created a significant national security vulnerability to the United States."