Children's shoes crowd the sidewalk at the Philadelphia immigration protest.
CNN  — 

As an Orthodox Jew, Sara Atkins says she grew up seeing images of children in Nazi concentration camps in World War II. If her great-grandparents hadn’t gotten sponsorship to enter the United States legally, she would not be here, the 38-year-old said.

She took to the streets of Philadelphia Tuesday evening, holding her 12-year-old daughter Freida by the hand, and joined a protest against President Donald Trump’s zero tolerance immigration policy.

Children’s shoes lined Rittenhouse Square, a minute away by car from the Rittenhouse Hotel, where Vice President Mike Pence was attending a fundraiser for Pennsylvania’s Republican gubernatorial candidate. Seeing the shoes stirred images of the camps in Atkins’ mind.

“I thought ‘Oh my gosh, this has happened before,’” she said. “Never again should really be never again.”

The protest, called “Pence in PHL: Stop Separating Families! Trump/Pence Must Go!” was organized by several groups, including Juntos (“together” in Spanish), the Youth Caucus of America, Philly UP and Refuse Fascism Philly.

“We’ve seen the outrage,” said Erika Almiron, the executive director of Juntos. “We wanted to let Pence know we stand against the separation of children at the border.”

The Trump administration announced the zero tolerance policy in May, saying authorities would criminally prosecute anyone who crosses the border illegally. The result: While they face prosecution, parents are now held in federal prisons – where their children can’t be held with them. Federal officials say at least 2,000 children have been separated from their parents.

According to Almiron and Youth Caucus of America CEO Coby Owens, several thousand people attended the event and shut down several blocks. Owens said his organization bused people from nearby states to attend the protest.

“Immigrant children are a part of our community,” he said. “We are going to fight for all our youth.”

A report published earlier this year by ProPublica found that Philadelphia’s Immigration and Customs Enforcement office, which also operates in Delaware and West Virginia, arrested the highest number of undocumented immigrants without criminal convictions in the country.

Protesters in Philadelphia hold signs expressing their opposition to the Trump administration's zero tolerance immigration policy

Almiron, Owens and Atkins said Philadelphia will never support the separation of families at the US-Mexico border.

“Philadelphia is ‘The City of Brotherly Love,’” Owens said. “We are all so different, but we are all Americans. … What Pence has failed to realize is making America great isn’t segregating it or dividing it. Diversity is what makes America.”

Atkins recalled the love and care people attending the demonstration showed one another.

“There was an overwhelming power of ‘we are one,’ ‘we’re going to fight for our democracy,’” she said. “I was able to hold onto (Frieda) and that was powerful, because these moms at the border can’t.”

CNN’s Catherine Shoichet contributed to this report.