Hundreds of people on Tuesday protested in New York, Washington DC, Los Angeles, Chicago and other US cities over the Trump administration's decision to end the so-called "Dreamers" program that allowed young immigrants who were brought into the country illegally as children to remain in the country.

The Deferred Action for Childhood Arrivals (DACA) program, created by former President Barack Obama, shielded the young recipients from deportation and allowed them to work in the country. 

Obama created the program through an executive order in 2012 after Congress failed to pass immigration reforms. It went on to help some 800,000 young people.

Confrontation outside Trump Tower

As anger spread over Trump's decision, police in New York handcuffed and removed over a dozen immigration activists who briefly blocked Fifth Avenue in Manhattan in front of Trump Tower.

In LA, police shut down intersections of busy roads as a march by hundreds of protesters proceeded. Many of them carried signs and chanted "Hey, hey, ho, ho, Donald Trump has got to go."

DACA was supported by Democrats and many business leaders, many of whom took to social media to decry the voiding of the program.

House Democratic leader Nancy Pelosi called Trump's decision "a deeply shameful act of political cowardice" and a "despicable assault on innocent young people in communities across America."

Mexican President Enrique Pena Nieto took to Twitter to voice his support for the migrants affected by the policy change.

"This measure will affect thousands of youths born in Mexico and living in the US since their childhood. We stand by them," he wrote.

Facebook founder Mark Zuckerberg decried the administration's decision on Tuesday, writing in a post on the social media site: "The decision to end DACA is not just wrong. It is particularly cruel to offer young people the American Dream, encourage them to come out of the shadows and trust our government, and then punish them for it."

Read more: 

'Dreamers' ready for fight to stay in US as DACA's fate looms

In announcing the decision on Tuesday, US Attorney General Jeff Sessions blamed Obama, saying he had overreached his authority by ignoring Congress over the matter.

"To have a lawful system of immigration that serves the national interest, we cannot admit everyone who would like to come here. It's just that simple. That would be an open-border policy and the American people have rightly rejected that," Sessions said.

Trump defends decision

Trump insisted in a statement he did "not favor punishing children, most of whom are now adults, for the actions of their parents. But we must also recognize that we are nation of opportunity because we are a nation of laws."

But his predecessor called the current president's decision "cruel" and "self-defeating." 

"Let's be clear: the action taken today isn't required legally," Obama said in a post on Facebook. "It's a political decision, and a moral question."

"Whatever concerns or complaints Americans may have about immigration in general, we shouldn't threaten the future of this group of young people who are here through no fault of their own, who pose no threat, who are not taking away anything from the rest of us," he wrote.

What happens to the 'Dreamers' now? 

Sessions said that the Trump administration would "wind down" the program as participants' authorizations expire, which could last until 2019. Administration officials said no current "Dreamers" would be affected before March next year, but any new applications coming in after Tuesday will be ignored.

The Department of Homeland Security (DHS) told reporters that it would provide a time window for DACA recipients whose work permits expire before March 5, 2018, to renew those permits.

Those whose permits will expire must apply for renewal before October 5, the DHS officials said. Immigration officials estimate that the work permits of around 210,000 people will expire over the next few months.

But what happens when the permits eventually run out? Former DACA recipients whose work permits expire will be considered to be in the US without permission and would be eligible for deportation, DHS officials told reporters, albeit adding that they would be considered low-priority cases.

All eyes on Congress

Sessions said that the six-month phase-out period will provide Congress with a window to pass legislation on the matter.

The announcement came as a deadline set by a group of Republican state officials passed. The officials had said they would challenge DACA in court should Trump not rescind the program. But the president could now face legal action over the decision. On Monday, the US states of New York and Washington vowed to sue Trump if he decided to go through with plans to scrap the program.

"New York will not demonize diversity...If President Trump rescinds #DACA, we will sue," wrote Governor Andrew Cuomo on Twitter.

rs,mm/bw (AP, AFP, dpa, Reuters)