More than 140 protesters, including Maryland Del. Ana Sol Gutierrez (D-Montgomery) and dozens of labor and immigrant leaders, were arrested Thursday outside the White House while staging a sit-down rally to demand protection from deportation for millions of illegal immigrants.

The demonstrators, representing more than 20 organizations, said the arrests were part of a civil disobedience campaign aimed at putting pressure on President Obama to enact broad leniency for illegal immigrant families and workers as part of his announced review of U.S. immigration policies.

Organizers said several hundred demonstrators sat down in front of the White House, chanting and hanging banners and flowers on the fence. About 145 people were then peacefully handcuffed by the U.S. Park Police and taken in vans and buses to a detention facility in Anacostia. A U.S. Park Police official said most of the protestors paid a $50 fine for holding an unlawful demonstration and were released, but some were still being processed as of 5 p.m. He said there had been no difficulties or violence.

Gustavo Torres, executive director of the immigrant advocate group Casa de Maryland and Casa de Virginia, was one of those taken into custody. Before his arrest, he issued a statement calling on Obama to “do everything in his power to enact humane and compassionate administrative relief” that would end the “suffering of immigrant families facing separation” through deportation.

Shortly after his release at 4 p.m., Torres said he was planning to “keep up the fight to make sure the president announces a big administration relief for people. We are very committed.” He said the police arrests and procedures were orderly and calm.

A park police officer shouts commands as anti-deportation protesters demonstrate in front of the White House Thursday. (Kevin Lamarque/Reuters)

Other protesters who were photographed, placed in plastic handcuffs and taken into custody included Terry O’Neill, president of the National Organization for Women; Larry Cohen, president of the Communications Workers of America; and several illegal immigrants associated with Casa de Maryland and Virginia.

The protesters first gathered outside the headquarters of the U.S. Immigration and Customs Enforcement agency, in Southwest Washington, and marched to the White House, where the arrests began a few minutes after a group of them sat down.

Obama has said he plans to use executive action to make major changes in immigration policy after Congress failed to reach agreement this year on proposals for comprehensive immigration reform.

He is reportedly considering a combination of measures that would grant deportation relief for certain categories of illegal immigrants, and that would also increase the number of legal immigrants by adding more visas for highly skilled workers and family members of immigrants who are permanent residents or U.S. citizens.

The Obama administration has said it is concentrating its deportation efforts on illegal immigrants who commit other crimes, but advocates such as Torres and Gutierrez say that thousands of illegal immigrants who are otherwise law-abiding workers and parents have also been deported, dividing families who have been in the United States for years.

Obama previously granted deportation relief to hundreds of thousands of Latino youths who entered the country illegally as children but have maintained a clean record.