Thousands of people nationwide joined marches on Wednesday evening to protest the death of Freddie Gray under uncertain circumstances in a Baltimore police van after his arrest earlier this month.

The biggest march was in Baltimore itself, where several thousand peaceful, mostly young demonstrators walked through downtown to City Hall.

In New York, protesters gathered at Union Square, in Lower Manhattan, for a rally dubbed on a Facebook page, "NYC Rise up and Shut it Down with Baltimore."

“We call on New Yorkers from across the five boroughs, #BlackLivesMatter activists and organizations as well as all organizations that stand for social, economic, and racial justice to rally,” said the organizers.

Many of the Manhattan marchers chanted “I can’t breathe,” quoting Eric Garner, the black man whose death last year in a police chokehold in Staten Island launched several nights of protest nationwide after a grand jury decided not to indict the white police officer.

At the New York march, police arrested more than 60 people. There were smaller, mostly peaceful marches in Boston, Denver, Houston, Indianapolis, Minneapolis and Washington.

In the Boston gathering organized by Mass Action Against Police Brutality, hundreds of people who were accompanied by police who blocked traffic for them. The marchers chanted “No justice, no peace, no racist police” and some carried signs, including “Boston Stands With Baltimore” and “I do not mourn broken windows, I mourn broken necks.”

Among the rally speakers was Wayne Dozier, grandfather of D.J. Henry, a black college football player from Massachusetts who was shot by police in the suburbs of New York City four years ago.

“Just like a lot of other people who have lost loved ones to the police, it hurts,” Dozier said. “It’s not a black thing. It’s a society thing. We really have to change society’s projection of black men.”

Several dozen protesters returned to the streets for a second night in Ferguson, Missouri, where the fatal shooting of 18-year-old Michael Brown by white police officer Darren Wilson on Aug. 9, 2014 drew national attention to police use of deadly force, especially against black men and launched a coast-to-coast debate about race.

The protesters on Wednesday night chanted “No justice, no peace, no racist police." and "We are the revolution. They can't stop the revolution.” according to the St. Louis Post-Dispatch.

A Ferguson Police Department spokesman said three people were shot during protests Tuesday night and four police cars were damaged when they were pelted by rocks and chunks of asphalt thrown by demonstrators.

Tensions have remained high in the St. Louis region since Brown's death and since a St. Louis County grand jury and the U.S. Justice Department declined to prosecute Wilson, who resigned from the police force in November.

Al Jazeera with wire services