Trump billed the operation as a major show of force in an effort to “deport millions” of people in the country illegally as the number of Central American families crossing the southern border has skyrocketed.

Of those arrested, 18 were members of families and 17 were collateral apprehensions of people in the country illegally encountered by Immigration and Customs Enforcement officials. None of those arrested resulted in a separation of family, officials said.

While the operation was demonized by Democrats as a full-force effort to deport families and trumpeted by Republicans as a necessary effort to show there are consequences for people here illegally, career ICE officers described it as a routine operation, one expected to net an average of about 10 to 20% of targets.

It targeted families who had been ordered deported by an immigration judge in 10 cities around the country who were subjected fast-track proceedings. It was canceled once after media reports telegraphing when and where it would begin, though Trump announced it would be postponed following a phone call with House Speaker Nancy Pelosi who urged him to do so.

The second round began July 14 and again was met with media attention noting when it would begin, including from Trump who announced the date.

Acting Immigration and Customs Enforcement Director Matthew Albence conceded the number was lower than other operations. He said Trump’s comments didn’t hurt the effort because it had already been the subject of media reports for weeks.

But the overall publicity caused problems for an operation that relies largely on secrecy and surprise. Albence said the publicity made some officers targets, and they had to be pulled off.

Part of the reason other, similar operations, were more successful is because they were “done without a lot of fanfare and media attention,” Albence said. “That certainly, from an operational perspective, is beneficial.”

Another factor was weather; that operations were suspended in New Orleans because of the hurricane there.

And immigrant rights activists nationwide had the rare advantage of knowing when to expect increased immigration enforcement, and they pushed “know-your-rights” campaigns hard.

Any hint of ICE activity, including false alarms, brought out dozens of activists to investigate in several cities, including Houston, New York and Chicago. To inform the public, they used hotlines, text networks, workshops and promoted a smartphone app that notifies family members in case of an arrest.

In Chicago, even city officials got involved.

Two city aldermen started “bike brigades,” patrolling immigrant-heavy neighborhoods to look for ICE agents and warn others. Another, Alderman Andre Vasquez sought volunteers on Facebook to serve as “ICEbreakers.” Over the weekend, it was standing-room only at his ward office as volunteers walked the neighborhood handing out know-your-rights cards and recruited businesses to be on the lookout.

“We were seeing concern and people starting to panic,” he said. “We want to live in the kind of environment where we never have to worry about ICE and raids.”

Activists reported one clear success story in Nashville, Tennessee, on Monday. Neighbors noticed ICE surveillance in the area and helped a 12-year-old boy and man avoid arrest by calling others and then linking arms around their van. ICE officers eventually called off the operation to avoid escalation.

Advocates also said many immigrants simply stayed home.

During the first weekend, the raids were supposed to start some immigrant-heavy churches had noticeably lower attendance and attributed the fear of stepped up enforcement. Businesses in immigrant-heavy neighborhoods, including in Chicago, Atlanta and Miami, also reported very light traffic.

A separate operation targeting immigrants here illegally who had criminal convictions or charges netted 899 arrests.

Albence said both operations would be ongoing, stressing the importance of enforcement in the interior.

“Part of the way you stop people from coming is having a consequence to the illegal activity when you do come,” he said.

On Monday, the administration announced it would vastly extend the authority of immigration officers to deport migrants without allowing them to appear before judges. Fast-track deportations can apply to anyone in the country illegally for less than two years. Previously, those deportations were largely limited to people arrested almost immediately after crossing the Mexican border. Advocates said they would sue.

It was the second major immigration shift in eight days. Last Monday, the administration effectively banned asylum at the southern border by making anyone coming to the U.S. from a third country ineligible, with a few exceptions. Lawsuits are pending.

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