Thousands of people, including labor unionists, swelled the ranks of Occupy Wall Street protesters to march across Lower Manhattan Wednesday.

Protestors, many with union placards and some leaving work early, gathered at the group's encampment in Zuccotti Park and marched to Foley Square in the largest demonstration since the movement was launched on Sept. 17.

Foley Square was filled with thousands as speakers railed against what they called corporate greed and control of American politics.

Corporate greed has pulled every one of us here It's time not to occupy Wall Street, but to take back Wall Street, said Christopher Shelton, vice president of a Communication Workers of America local.

Participants included members of National Nurses United, the profession's largest U.S. union; Transport Workers Union Local 100, the Metropolitan Transportation Authority's biggest; and the Working Families Party, a coalition of more than 60 community organizations, the San Francisco Chronicle reported.

Patrick Bruner, a spokesman for Occupy Wall Street, said the turnout exceeded 15,000.

Working people are going to stand together until we get fair justice in our economy, said George Gresham, president of a Service Employees International Union local. We want to make sure our children have a future in this country that is not subservient to those who have more than they need.

An Occupy Wall Street Web site said the group hopes to emulate the Arab Spring revolutions and insists on nonviolence to maximize the safety of all participants.

AFL-CIO President Richard Trumka told the Los Angeles Times the labor movement joined the New York march to support Occupy Wall Street, not to usurp it.

“The labor movement had long backed the goals of Occupy Wall Street, including making the richest 1 percent of the population pay higher taxes to help the rest of the country,” he added.

Several labor speakers said that there should be unity between the unions and Occupy Wall Street, which has been a fairly nebulous movement with scattered goals and leadership.

As the march grew in numbers, since the movement was launched, cops with plastic handcuffs became ready to arrest the protesters Wednesday.

“Stay on the sidewalk! Stay on the sidewalk!” a police supervisor shouted at the crowd.

Protesters marched peacefully but as darkness fell police tried to stop protesters from advancing toward Wall Street.