The recent departure of a former US Immigration and Customs Enforcement spokesperson is putting a spotlight on the agency’s special operations — large, multi-day investigations that identify, arrest and deport people who are deemed a risk to public safety and have committed immigration violations.

James Schwab, who worked in ICE's San Francisco office, told reporters he quit last week because he could not defend "misleading" statements from high ranking officials about ICE’s most recent four-day operation in California, which resulted in 232 arrests.

In a press statement and in multiple interviews, Thoman Homan, acting director of ICE, said he believes 800 people were able to evade arrest because Oakland Mayor Libby Schaaf warned residents there could be a raid. ‘“She gave them warning and there’s 800 that we were unable to locate because of that warning,” he told "Fox & Friends."

Liz Johnson, a spokesperson for ICE, pointed to another interview on Fox News that indicates that the agency actually can’t put a specific number on how many targets avoided arrest, but that “many criminal aliens were not apprehended because of that warning.”

“The intent behind the comments is the same — it’s common sense that if you give a criminal a heads-up that law enforcement is looking for them, they will try to avoid arrest,” Johnson said in an email to PRI.

She maintained that Schaaf’s warning did have an impact on the operation, which targeted 1,020 people. Of those, 864 remain at-large. Johnson said the proportion of arrests reflects a lower percentage than most ICE operations.

Schwab also disputed officials' statements that 100 percent of those who were not arrested were dangerous criminals. Out of the 1,020 on the target list, 95 had pending or adjudicated criminal charges or unconfirmed criminal convictions, according to Johnson.

Also: When Homan visited California last year, he was met with protests

The back-and-forth between Schwab, ICE officials and government officials in California provides a glimpse into the agency’s enforcement and removal operations, how their tactics have shifted during those operations and how communities are reacting to them.

On the one hand, immigrant advocates and observers said enforcement tactics of the agency have changed under the Trump Administration. Arrests by the agency increased by 30 percent in fiscal year 2017, according to a study by the Pew Research Center.

Immigrant advocates and analysts attribute that jump to the agency casting a wider net and arresting people whose only offense is breaking immigration laws.

Doris Meissner, a senior fellow at the Migration Policy Institute and a former commissioner of the US Immigration and Naturalization Service (a precursor to today's ICE, Citizenship and Immigration Services and Customs and Border Protection) during the Clinton administration, said the majority of people who are arrested have criminal backgrounds. But a “growing proportion” of those arrested are people who don’t have a criminal history, she said.

“People who are not expecting enforcement are suddenly faced with enforcement,” she said.

An executive order signed by President Trump in Jan. 2017 stated that agents can prioritize deportation of any “removable” undocumented immigrant who poses a risk to public safety or national security according to the judgment of an immigration officer.

ICE said it’s been able to shift more resources toward interior enforcement due to a drop in border crossings in recent years.

More about the homeland security budget.

In many ways, though, ICE operations have remained the same. Staffing levels, which include deportation officers, criminal investigators and support staff, have not increased proportionally to the increase in arrests. There were 19,276 ICE agents in fiscal year 2016, and 19,776 in 2017, according to numbers provided by ICE.

While Trump’s executive order in January 2017 called for an increase in the number of immigration officers by 10,000, the budget for 2018 only requested 1,606 new personnel. But both figures are ambitious and would require time and recruitment, according to Meissner. She said any increase in the number of ICE agents will be gradual.

“As a practical and operational matter, it's going to take quite a few years to reach that goal — if it's reached at all,” Meissner said.

ICE’s recent operations, especially in so-called “sanctuary states” like California, are also being scrutinized by immigrant advocates. But, they said arrests by ICE first reached historic levels during the Obama administration.

“The fact of the matter is that the Obama administration's record ... is one that also saw many hundreds of thousands of individuals who were apprehended and removed who had no criminal history,” says César Cuauhtémoc García Hernández, an associate professor at the University of Denver Sturm College of Law and author of the Crimmigration blog.

But, García Hernández said the Trump administration seems to want to go beyond what Obama’s administration did.

“The Trump administration is much more willing to apprehend absolutely anyone and everyone who comes across an ICE agent’s path, who is potentially removable from the United States,” he said. “[The Trump administration is] much more willing to detain individuals and much more willing to use bombastic flamboyant rhetoric about the public safety threat that some migrants present.”

An official with the Department of Homeland Security told the New York Times that it is normal for immigration enforcement operations to net about 30 percent of their intended targets, which would be about 300 in the northern California raid.

Despite this, Attorney General Jeff Sessions continued to hammer Oakland’s mayor for warning residents about the special operation. During a speech in Sacramento, California on March 7, he said: "According to Acting Director Homan, ICE failed to make 800 arrests that they would have made if the mayor had not acted as she did. Those are 800 wanted aliens that are now at large in that community — most are wanted criminals that ICE will now have to pursue with more difficulty in more dangerous situations, all because of one mayor’s irresponsible action. So here’s my message to Mayor Schaaf: How dare you. How dare you needlessly endanger the lives of law enforcement just to promote your radical open borders agenda."

President Trump also hammered the Oakland mayor saying: “They had close to 1,000 people ready to be gotten, ready to be taken off the streets ... they say 85 percent of them are criminals and had criminal records. And the mayor of Oakland went out and warned them, scattered, so instead of taking in a thousand they took in a fraction of that.”

Schwab, the former ICE spokesperson, maintained that the 800 figure is misleading.

“We were never going to pick up that many people. To say that 100 percent are dangerous criminals on the street, or that those people weren’t picked up because of the misguided actions of the mayor, is just wrong,” Schwab told the San Francisco Chronicle.

These special operations will likely continue, especially in so-called sanctuary states.

“There is definitely an effort being made at the federal level and certainly by the political leadership in this administration to be particularly focused on states and communities that have adopted policies of non-cooperation,” said Meissner.

From PRI's The World ©2017 PRI