More than 2,000 migrants who were in the United States illegally were targeted in widely publicized raids that unfolded across the country last week. But figures the government provided to The New York Times on Monday show that just 35 people were detained in the operation.
President Trump had touted the raids — called Operation Border Resolve — as a show of force amid an influx of Central American parents and children across the southern border. After postponing the raids in June, Mr. Trump said ahead of time that they would take place last week.
Two current Department of Homeland Security officials and one former department official also confirmed to The Times that an enforcement operation would take place around mid-July.
But the publicity may have prompted many of those who had been targeted — 2,105 people in more than a dozen cities who had received final deportation orders but had not reported to Immigration and Customs Enforcement officers — to temporarily leave their homes, or to move altogether to evade arrest.
Advance notice of the large-scale operation also gave immigrant advocates time to counsel families about their rights, which include not opening the door or answering questions. On social media, community groups shared detailed information about sightings of ICE agents.
In an interview Monday, Matthew Albence, the acting director of ICE, which is responsible for arresting, detaining and deporting unauthorized immigrants who are already in the United States, acknowledged that the number of apprehensions was low.
“I don’t know of any other population where people are telling them how to avoid arrest as a result of illegal activity,” he said. “It certainly makes it harder for us to effectuate these orders issued.”
“You didn’t hear ICE talking about it before the operation was taking place,” he added.
The arrests of the nearly three dozen migrants — 17 of whom were members of families that crossed the border together and 18 of whom were so-called collateral apprehensions of undocumented people — were among more than 900 that the immigration authorities have made since mid-May, Mr. Albence said.
From May 13 through July 11, ICE arrested 899 adults who had final deportation orders, in an undertaking called Operation Cross Check. The majority had criminal convictions, Mr. Albence said.