Waving U.S. and Mexican flags, thousands of people marched through downtown New Haven late Monday afternoon and staged a rally on the New Haven Green to protest pending legislation on immigration reform.

The New Haven events were part of the national “A Day Without Immigrants,” which brought hundreds of thousands of activists–many of them immigrants–out to rallies in cities across the nation to show the importance of immigrants to economic and social life in the United States. Congressional debate on new immigration legislation has been stalled in recent weeks due to conflict within the Senate and between the two houses of Congress.

In New Haven, Monday’s protest was organized by a coalition of community and student groups — including Unidad Latina en Accion, Movimiento Estudiantil Chicano de Aztlan and the Yale Latino Law Students’ Organization — that favor a path to citizenship for illegal immigrants currently in the country.

“We don’t believe criminalizing everybody is the answer,” Unidad member John Jairo Lugo said.

Lugo said a guest worker program would create a group of “second-class citizens.” Employers would have more freedom to abuse workers whose presence in the country depended on their having a job, he said.

“It’s going to be some kind of slavery,” Lugo said.

The House passed an immigration reform bill in December that would tighten border security and make it a felony to be present in the United States illegally. A bipartisan Senate compromise, which fell apart earlier this month, would create a path for illegal immigrants to move toward citizenship while also tightening border controls to prevent future immigration.

Friday’s events were linked to May Day rallies celebrating International Workers’ Day that took place on the Green in the morning. The march for immigration rights, which organizers said drew about 5,000 people, began at about 5:30 p.m. and snaked from the Green to York St. and back. Afterwards, a band played and organizers spoke to a smaller crowd gathered on the Green.

Many of the marchers were families, some pushing small children in strollers. They waved flags representing the United States, Mexico, Ecuador and Guatemala, while chanting “Si se puede.” MEChA moderator Adriana Garcia ’08 said the chant translates roughly to “It can be done,” and comes from Cesar Chavez’s labor organizing.

Garcia and Lugo said the rally came together through the outreach efforts of individual community groups, including churches, and the distribution of flyers throughout New Haven.

“The reason why this is so massive today is the power of word of mouth,” Garcia said.

Simon Moshenberg LAW ’08, the incoming chair of the Workers’ Rights Project at the Law School, said the goal of Friday’s march and rally was to double the number of participants from the last major rally on April 10. He estimated that about 10,000 people participated in the immigration rights events held Friday afternoon and evening, compared to 5,000 last month. Two hundred Yale students met at the Law School and marched across Old Campus on the way to the Green, he said, which was four times the number of students who participated in April.

Yale unions, including the Graduate Employees and Students Organization, also provided resources for the rally and helped encourage turnout, GESO member Gahodery Rodriguez GRD ’06 said.