Demonstrations have taken place across the nation following the May 25 killing of George Floyd in Minneapolis, and Cambridge has joined the list.

A protest took place Saturday at the corner of Route 50 and Maryland Avenue, as local citizens voiced their anger and grief at the deaths of black men in police custody.

On Friday afternoon, a 37-year-old Easton man, Larry D. Ross Jr., died in the custody of the Maryland State Police, who had conducted a traffic stop. State Police and local agencies are investigating the death.

Former Minneapolis officer Derek Chauvin has been fired from that city’s police department. He was charged with third-degree murder and manslaughter after kneeling on Floyd’s neck for almost nine minutes.

The cases join a yearslong record of controversial deaths of African-American men while in police custody. In recent years, there has been increased publicity as bystanders record incidents and share them online.

Graphic images of Floyd’s death have circulated for days, helping to fuel outrage. Though some of the protests around the nation have turned violent, the one in Cambridge was peaceful.

Hand-drawn signs displayed for motorists to see had messages including, “Black lives matter,” “No respect for existence, expect resistance,” and “Work for justice.” One man wore a shirt saying, “I can’t breathe,” recalling some of the last words of Floyd and a man in a similar incident in New York City, Eric Garner.

Participants were black and white, as were the drivers who passed on the highway blowing their horns and waving in support. An observer at the location did not see or hear opposition from anyone on the road.

The 3 p.m. event on Saturday came together quickly, organized by Tyzann Meekins, Wendy Appollos and Cierra Desravine beginning late that morning.

“We need to take a stand,” Ms. Meekins said, adding that the latest incidents were “too many times.”

Susan Olsen is a local resident, a woman of European descent who is also a member of the National Association for the Advancement of Colored People.

“People need to know black lives are just as important as other lives,” she said. Looking at the crowd on the corner holding up their signs, and remembering the civil rights movement and its results, she said she thought the issue had been settled in the 1960s.

“I can’t believe this still exists,” she said.