A nationwide campaign by Immigration and Customs Enforcement to round-up and deport immigrant families will  start on Sunday. The raids have been discussed for some time already but were postponed on the president’s orders pending a legislative solution from Congress.

The raids will be conducted in 10 cities over multiple days and will include “collateral” deportations and detention, in which other immigrants than the intended targets of the raid will be arrested and possibly deported.

The operation has been announced before, including by the president over Twitter, but has been delayed or postponed. Resistance to the raids by Democratic politicians has been strong. The previous postponement was partially blamed on operational details being leaked by the president, who took flak from acting ICE Director Mark Morgan for doing so. “It’s just egregious, and it puts the lives of the officers and agents at risk,” Morgan said in an interview on Fox News. “The men and women I’ve served with are true American heroes. And so what the President did — he recognized that, and so he postponed … to protect them.”

Obama administration acting ICE Director John Sandweg also expressed concern over the publicization of the raids.”You never want the target to know you’re coming. You want that element of surprise because it keeps you safe,” he said, referring of course to the officers’ safety, not the migrants. “Somebody has determined the political value of talking about this publicly exceeds the operational value of surprise.”

This time it seems no delays are expected. On Wednesday, acting US Citizenship and Immigration Services director Ken Cuccinelli vowed that the raids are “absolutely going to happen.” “There’s approximately a million people in this country with removal orders. And of course, that isn’t what ICE will go after in this, but that’s the pool of people who have been all the way through the due process chain,” Cuccinelli stated.

The raids are set to be executed in Atlanta, Baltimore, Chicago, Denver, Houston, Los Angeles, Miami, New Orleans, New York and San Francisco, although the city of New Orleans posted on Twitter that “immigration enforcement will be temporarily suspended through the weekend” in areas of Louisiana and Mississippi impacted by tropical storm Barry.”

Migrant families and the immigrant community at large have been thrown into panic, with many who are anxious about potentially being targeted already going underground, or leaving their homes to stay with relatives and friends. Immigrant advocacy groups have been disseminating information and making resources available for several weeks now, due to the delay, which some see as a blessing in disguise.

“We tell people to know their rights, to know that they don’t have to tell anyone their immigration status, they don’t have to open the door for anyone unless there is a signed warrant by a judge,” said Andrea Guttin, legal director at Houston Immigration Legal Services Collaborative. Other groups, such as the ACLU, have also aided in informing targets of the raids of their rights.