The unusually large demonstration for Philadelphia, which was comprised mostly of African Americans, followed protests in Florida and New York.
The protests are dubbed “Million Hoodie Marches” in memory of the victim, 17-year-old Trayvon Martin, who was reportedly wearing a hoodie sweatshirt when he was shot last month in a gated community by a white volunteer security guard.
Fritz Andre, 24, a data analyst, said he joined the rally because “it’s one of those one in a lifetime, generational moments. Our forefathers had it, and you don’t want those to pass.”
Another marcher, Fred Mac, 23, said: “This could be anybody. Tryavon could be you bother, your neighbor, your son.”
“It touched me. I have three boys that I'm scared to let walk the street,” said Lynay Goodman, 29.
Reggie Conquest, 24, explained the symbolism of the hoodie and the suspicions that many black men face in urban settings.
“Being a big black guy, people get startled. They walk across the street. I’m a nice guy. When I see that, I take off my hoodie. I don't want to startle nobody,” he said.
Late Thursday, up to 20,000 people rallied in the Florida town of Sanford, where Martin was killed by George Zimmerman.
Protesters have claimed that Martin’s killing is just the last example of racial profiling and unjust treatment of blacks by the country’s criminal justice system.
Zimmerman, who says he acted in self-defense after a confrontation with the teenager, has not been arrested.
On Friday, President Barack Obama entered the controversy, urging “soul searching.”