Echoing activists who are pushing for a pathway to citizenship for the nation’s millions of undocumented immigrants, Facebook co-founder Mark Zuckerberg said that overhauling U.S. immigration laws is a modern-day civil rights issue.

Zuckerberg, who has been an increasingly vocal advocate for more flexible immigration laws, said in an interview on ABC News' “This Week” that many of the estimated 11 million undocumented immigrants in the United States come with noble objectives. The 29-year-old billionaire said they should be given an opportunity to legalize their status.

His advocacy efforts on immigration have focused on the expansion of visas for high-tech workers and a path to legal status for undocumented immigrants brought to the United States as minors.

“When you meet these children who are really talented, and they’ve grown up in America and they really don’t know any other country besides that, but they don’t have the opportunities that … we all enjoy, it’s really heartbreaking – right? That seems like it’s one of the biggest civil rights issues of our time,” Zuckerberg said in the interview.

Zuckerberg just hosted a marathon computer coding session for 20 undocumented immigrants – made up generally of college students – who beat out hundreds of applicants for a chance to participate in the so-called “hackathon.” 

The immigrants, known as “Dreamers” after the DREAM Act – a proposed federal measure that gives legal residency to certain qualifying young immigrants – worked with engineers and coders from various companies to develop programs targeted at immigration reform.

Zuckerberg and others – such as Dropbox and LinkedIn top executives – then picked three winning projects from about eight that were presented by the immigrant teams. Those winning teams will receive technological support to develop the ideas.

That outreach by Zuckerberg has won plaudits from many immigrant advocates, but the president of the union representing immigration enforcement officers criticized the Facebook chief executive for not responding to the group’s request for a meeting and for rewarding lawbreakers.

“Earlier this month, we sent a letter to the major CEOs pushing a comprehensive immigration plan asking that they meet with ICE officers,” said Chris Crane, president of the National ICE Council, in a statement.

One of those on the letter was Mark Zuckerberg. . . Mr. Zuckerberg ignored the letter and meeting request from ICE law enforcement and instead met with illegal immigrants.”

“We respectfully renew our request to meet with Mr. Zuckerberg and share firsthand the knowledge and experience of ICE officers and agents. . .Until Mr. Zuckerberg meets with officers and learns the truth about our immigration system, I would respectfully suggest he suspend his lobbying activities."

In the ABC News interview, Zuckerberg said the United States would benefit from making its immigration laws more flexible.

“The future of our economy is a knowledge economy. And that means that getting the most talented people into this country is the most important thing that we can do to make sure that the companies of tomorrow are founded here,” Zuckerberg said in the interview.

As for the undocumented immigrants who lack high-tech skills or college degrees, Zuckerberg said they raise the children who end up talented enough to keep the United States globally competitive.

“One of the things that the ‘Dreamers’ here today show is that even if, you know, you’re a child of someone who came here who wouldn’t be considered one of the higher-skilled workers … you can be one of the entrepreneurs of tomorrow,” Zuckerberg said, referring to the participants of the hackathon. “That’s the American dream.”