Federal immigration officials detained an undocumented woman from Falls Church who came to their offices for a routine check-in on Thursday, drawing angry protests from advocates who say President Trump should focus on deporting those who pose a public-safety threat.

The arrest of Liliana Cruz Mendez, 30, a mother of two from El Salvador, comes a day after U.S. Immigration and Customs Enforcement released statistics showing a significant increase in deportation arrests since Trump’s inauguration, mostly involving undocumented residents with criminal records.

While immigration hard-liners are applauding Trump’s efforts, advocates for those here illegally say ICE is defining the term “criminal” so broadly that many minor offenders — including Cruz Mendez, who has a misdemeanor conviction for driving without a license — are being torn from their U.S.-born children.

The agency also more than doubled the arrests of noncriminal immigrants, to nearly 11,000, about a quarter of the arrests reported Wednesday.

“This is the real face of what ICE is doing,” said George Escobar, senior director of human Services for CASA, a Maryland-based nonprofit that is aiding Cruz Mendez. “They are shattering families and children’s lives.”

CASA originally said that Cruz Mendez had never been convicted of a crime. However, Fairfax County court records show the driving infraction from 2013. Her lawyer said the offense was not serious enough to warrant her ouster, noting that Cruz Mendez qualified for stays of deportation in 2014 and 2015.

Immigration officials also confirmed reports on Thursday that ICE is reactivating long-dormant deportation cases that were closed under the Obama administration because they involved individuals who were not serious criminals or otherwise a priority for ouster.

Court records show that tens of thousands of such cases were administratively closed without deportation proceedings during Obama’s tenure, using a process known as “prosecutorial discretion.”

ICE spokeswoman Jennifer Elzea did not say how many cases have been placed back on the docket. But she said the reopened cases involve immigrants who have “since been arrested for or convicted of a crime.” ICE “generally reviews” closed cases to determine if the closure is “still appropriate,” Elzea said.

Immigration lawyers said they were aware of scores of reopened cases — and not always involving criminals.

In Detroit, a lawyer said he had three cases reopened that involved traffic stops. In Orlando, a longtime immigration lawyer said he knew of dozens of cases that had been reopened.

“It’s happening, but it’s very hush-hush. Details are hard to come by,” said the Orlando attorney, who spoke on condition of anonymity because he feared retaliation.

Dana Leigh Marks, president of the National Association of Immigration Judges, said the immigration court’s docket is bursting at historic highs, and cannot easily absorb a flood of reopened cases.

Marks, who is based in San Francisco, said she is scheduling cases into 2022. “We’re teetering on the point of implosion,” she said. Trac, a Syracuse University organization, said there are nearly 600,000 pending deportation cases.

But Don Rosenberg, a father who lives outside of Los Angeles, said it is unfair to dismiss any illegal immigrants — including unlicensed drivers as minor offenders. His son Drew was killed in 2010 by an unlicensed driver from Honduras who came to the United States illegally and then secured temporary permission to stay.

“She may not have had the opportunity to say goodbye to her family, but she can still speak to them and see them,” he said of Cruz Mendez. “I never got to say goodbye to my son.”

Cruz Mendez came to America in 2006, when she was 18, to join a brother living in Virginia, CASA said. She been threatened by an older man who once held a pistol to her head to coerce her into having a romantic relationship.

She was caught crossing the border illegally and released. Seven years later, Cruz Mendez was stopped by police in Fairfax County for allegedly driving without headlights. She had an outstanding deportation order and did not have a license, CASA said. She ended up in ICE’s custody.

By then, Cruz Mendez was married and had two children, including an infant who was breast-feeding. She released after three days, and had to check in with ICE at regular intervals.

Thursday was the first check-in since Trump took office.

Advocates from CASA accompanied her and her family to the ICE offices in Fairfax, and launched an immediate social media and public relations campaign when she was arrested.

Late Thursday afternoon, two dozen supporters held a rally outside the ICE offices to demand her release. They shouted “Shame on you!” and “Not one More!”

“This is so wrong,” said Nancy Bleeker, who lives in McLean and heard about Cruz Mendez’s arrest through her synagogue, Temple Rodef Shalom. “It’s not what our country stands for.”

Rene Bermudez, Cruz Mendez’s husband, stood nearby with their daughter Danyca, 4. Their son, 10 was not with them.

Bermudez said his wife expressed fear of returning to El Salvador, which has been ravaged by gang violence and has one of the highest homicide rates in the world.

Sens. Tim Kaine and Mark R. Warner and Rep. Gerald E. Connolly, all Democrats from Virginia, released statements saying they would seek more information about the arrest.

“Liliana is a mother of two American children and poses no public safety or national security threat,” Connolly’s statement said. “I won’t stand by silently while this administration seeks to break up Northern Virginia families.”

Michael E. Miller and Jenna Portnoy contributed to this report.