Two senior Homeland Security officials tell NBC News that nationwide arrests of undocumented immigrants are scheduled to start Sunday.

The raids will be conducted by immigration and customs enforcement in at least 10 major cities, including Los Angeles, Chicago, Atlanta, Miami and New York.

ICE won’t comment on enforcement operations.

Across the country, swift outrage. Several protesters arrested in Buffalo, New York.

The President had postponed the roundup, but last week said it would begin “fairly soon.”

“I say they came in illegally, and we’re bringing them out legally,” President Trump said last week.

Hiba Ghalib is an immigration attorney in Atlanta who explained what she’s telling her clients.

“We’re telling things to them like don’t answer your door if someone knocks in the middle of the night. If they are an official from the government, they need to have a warrant if they are going to come to your home.”

Stephanie Lopez is a DACA recipient who worries about who’d care for her young siblings if her undocumented parents were deported.

“I think that's what the problem is it just creates a lot of fear and no one knows if they are going to knock your door next

Families arrested in the sweep could be flown to detention centers in Texas and Pennsylvania while they await deportation. Plans are still being finalized.