Matt Rourke, Associated Press
Protesters rush a police line after a rally at City Hall in Philadelphia on Thursday, April 30, 2015. The event in Philadelphia follows days of unrest in Baltimore amid Freddie Gray's police-custody death.

LOS ANGELES — Marches and rallies in U.S. cities on Friday drew crowds ranging from a few dozen to hundreds of people demanding more rights for workers and immigrants and an end to police brutality.

Demonstrations were held in cities from Minneapolis to Oakland, California. In Denver, two dozen protesters railed against economic inequality, while 1,000 marched in New York at an event that also decried police abuse in the wake of the in-custody death of Freddie Gray in Baltimore.

In Chicago, about 400 people marched, some to protest recent police incidents and some to recognize May Day's message of workers' rights.

Richard Malmin, a 73-year-old activist, said he participates every year but this rally was bigger due to the death of Gray, whose spine was severed while in Baltimore police custody last month. On Friday, six police officers were charged in his death.

"This is a turning point, a tremendous turning point that shows finally the country is waking up," Malmin said. "This is a first, really."

While labor unions have long led demonstrations on International Workers' Day, the May 1 marches got a boost in 2006 when stringent immigration legislation drove hundreds of thousands of demonstrators to rally in the streets. Since then, attendance at the annual rallies has been much smaller.

Some labor and immigrant advocates broadened their message this year to also address police brutality, joining a series of protests underway in several cities over Gray's death.

In Minneapolis, the group Black Lives Matter encouraged students to leave school on Friday, and some high school students did. They staged a die-in that briefly stopped traffic.

More than 1,000 people demonstrated in Oakland, California, with some holding signs saying "Racism is the Disease" and "Stop Police Brutality." Others said they wanted better wages and working conditions for the masses.

Hundreds gathered in Seattle for an annual worker and immigrant rights rally. In Los Angeles, a few hundred gathered to encourage the implementation of President Obama's program to protect millions of immigrants in the country illegally from deportation. They also called for a raise to minimum wage.

Associated Press writers Don Babwin in Chicago, Kristin Bender and Olga Rodriguez in San Francisco, Edwin Tamara in Los Angeles, and Michael Balsamo and Jake Pearson in New York contributed to this report.