Demonstrators demanded an overhaul of US immigration laws today in an annual nationwide ritual that carried a special sense of urgency as Congress considers sweeping legislation that would bring many of the estimated 11 million people living in the US illegally out of the shadows.
May Day rallies were planned in dozens of cities from New York to Bozeman, Montana.
"The invisible become visible on May 1," said Angelica Salas, executive director of the Coalition for Humane Immigrant Rights of Los Angeles, which organised what was expected to be the nation's largest rally.
The crowds were not expected to approach the massive demonstrations of 2006 and 2007, during the last serious attempt to introduce major changes to the US immigration system.
Immigration reform gained little traction in Congress during President Barack Obama's first term, but the November election brought some opposition Republicans to the issue after they watched the growing number of Hispanic voters overwhelmingly side with Obama and Democrats.
A bill now being crafted in the Senate would strengthen border security, allow tens of thousands of new high- and low-skilled workers into the country, require all employers to check workers' legal status and provide an eventual path to citizenship for immigrants now in the country illegally.
The May Day rallies, which coincide with Labor Day in many countries outside the US, often have big showings from labor leaders and elected officials.
Salas, whose group is known as CHIRLA, dates the rallies to a labor dispute with a restaurant in the Los Angeles Koreatown neighbourhood that drew several hundred demonstrators in 2000. Crowds grew each year until the House of Representatives passed a tough bill against illegal immigration, sparking a wave of enormous, angry protests from coast to coast in 2006.
