Tens of thousands of demonstrators rallied on the National Mall and marched through the streets of the capital Sunday, waving American flags and holding homemade signs in English and Spanish.

WASHINGTON (AP, Reuters) – Frustrated with the lack of action to overhaul the country’s immigration system, tens of thousands of demonstrators rallied on the National Mall and marched through the streets of the capital Sunday, waving American flags and holding homemade signs in English and Spanish.

Supporters traveled from around the country in hopes the rally would re-energize Congress to take up the volatile issue. Some lawmakers oppose any attempt to help an estimated 12 million illegal immigrants become US citizens while others insist on stronger border controls first.

Carrying signs that said “Justice and Dignity for All U.S. Immigrants” and “We just want to work,” the immigration activists filled five blocks of the National Mall. Some protesters wore T-shirts that read, “Our journey as immigrants is a journey for human rights.”

President Barack Obama, who promised to make overhauling the immigration system a top priority in his first year, sought to reassure those at the rally with a video message presented on giant screens at the National Mall. The president said he was committed to working with Congress this year on a comprehensive bill to fix a “broken immigration system.”

Obama said problems include families being torn apart, employers gaming the system and police officers struggling to keep communities safe.

The president, whose comments were released as he worked to get last-minute votes on a health care overhaul, said he would do everything in his power to forge a bipartisan consensus on immigration reform. The House was expected to vote on the landmark health care legislation late Sunday.

Some demonstrators were disappointed there hasn’t been more action a year into Obama’s term.

“I understand it may not all be his (Obama’s) fault,” said Manuel Bettran, a 21-year-old college student from Chicago. “I am frustrated. I really wish not just him, but everybody, would take it more seriously. “

Bettran arrived in Washington on Sunday morning after a 13-hour bus ride. Like many, he had a personal connection to the issue. His parents were once illegal immigrants but were able to take advantage of an amnesty in the 1980s.

“Fortunately, they were able to become citizens during the last amnesty, but I know many people that weren’t that lucky,” said the American-born Bettran, adding that his brother was never able to gain legal status and had to leave the US.

Lawmakers failed to agree in 2006 and 2007 when they last tried to overhaul the immigration system, and the political climate is even tougher now.

Sens. Chuck Schumer (Democrat-New York) and Lindsey Graham (Republican-South Carolina) released an outline of a bill last week that calls for illegal immigrants who want to get on the path to legal status to admit they broke the law by entering the US, pay fines and back taxes, and perform community service. They also would be required to pass background checks and be proficient in English before working toward legal residency, required before becoming a citizen.

Ben Jealous, president of the National Association for the Advancement of Colored People and a speaker at the rally, said the activists no doubt got the attention of lawmakers by converging on the mall “on the one Sunday Congress was in session.”

“I think you’ll see a response in the following weeks,” he said.

Authorities in DC (District of Colombia) don’t provide crowd estimates, but the mall was full of people for three blocks.

People held signs with slogans such as, “You need us as much as we need you,” and “No Human Being is Illegal.” Many waved American flags, and a few also carried the banners of their countries of origin.

One group from Queens, New York, displayed a giant papier-mache family — a mother and two crying children. The creation, meant to symbolize the way immigration problems have split up families, was the work of teenagers in an after-school program, said Natalia Aristizabal, arts and media educator for the group, Make the Road New York.

New York Democratic Representative Nydia Velazquez said: “Every day without reform is a day that 12 million hard-working immigrants must live in the shadow of fear, and ... a day that a family is torn apart. That is wrong and it is unAmerican.”

Velazquez, who chairs the Congressional Hispanic Caucus, called on Congress and the president to reform immigration laws immediately.

Immigration is a sensitive issue in the United States where some 10.8 million illegal immigrants live and work in the shadows and where Hispanics, the largest immigrant group, are a rapidly increasing voting bloc.