Thousands protested in cities across the US against the acquittal of neighborhood watchman George Zimmerman, a day after his trial for killing unarmed black teenager Trayvon Martin ended in Florida.
Demonstrators rallied noisily, but peacefully, in US cities including New York, San Francisco, Boston and Chicago.
In Los Angeles, police in riot gear deployed along Hollywood Boulevard, but they were not needed as the rally proceeded without incident. But about 150 protesters blocked traffic on a freeway elsewhere in the city, local media reported.
In the pre-dawn hours demonstrators smashed windows and vandalized cars in Oakland, California.
Spontaneous marches were also held in Washington, Philadelphia, Atlanta and the Florida state capital Tallahassee.
The most numerous rally was in New York City, where several thousand -- including families with children -- marched to Times Square under the watchful eye of police.
Many in the multi-racial crowd brandished signs bearing a portrait of Martin, while some, despite sweltering July heat, wore "hoodie" sweatshirts, as the 17-year-old did the night he was killed in February 2012.
"I am appalled," said Carli VanVoorhis, a 21-year-old hairdresser.
"The man was armed, the kid was not, and the man with the gun got away," she said. "If we say it was not a racial issue, we would be lying."
Chants included "the people say guilty!" and "No justice, no peace!"
One sign urged: "Jail racist killers, not black youth," while others declared "We are all Trayvon. The whole damn system is guilty."
At least one marcher wore a T-shirt proclaiming: "I'm black. Please don't shoot."
"We have a big problem with race, and another problem is guns," said protester Rodney Rodriguez. "If Zimmerman didn't have a gun, he couldn't have killed Trayvon Martin."
Fellow protester Derreck Wilson, 46, said the group had come "to say in a peaceful way why we are angry. We are angry, scared and anxious."
"It's cathartic," he said.
"We all have the same desires. I want to be able to have my son to come home," added Wilson, who came to the protest from the traditionally African-American neighborhood of Harlem.
Rhada Blank also came from Harlem with friends.
When the verdict was announced, she said she thought about leaving the United States permanently.
"I was sick to my stomach when I heard the verdict, I felt ashamed," she said. "I don't feel good about being American today. I think we have a lot of work to do."
"As far as people think we've gone, with the decision of electing (President Barack) Obama, this verdict shows we haven't moved beyond race," said the former teacher who now writes for the theater.
"People have not moved beyond their fears," she said. "That decision echoed what many people are feeling in the country. There is a fear of the black male."
The case has, since the beginning, pitted those who belive that Zimmerman, a 29-year-old Hispanic neighborhood watchman, killed Martin in self-defense, and those who believe it was a murder sparked by racist assumptions.
According to Florida's controversial "Stand Your Ground" law, people who fear for their lives can use deadly force to defend themselves without having to flee a confrontation. Other states, including Texas, have similar rules.
The killing also resonated among those calling for stricter gun laws like New York Mayor Michael Bloomberg, who slammed what he called "shoot-first laws."
"Sadly, all the facts in this tragic case will probably never be known. But one fact has long been crystal clear: 'shoot first' laws like those in Florida can inspire dangerous vigilantism and protect those who act recklessly with guns," Bloomberg said in a statement.
He reiterated his call to eliminate such laws.
"The tragic death of Trayvon Martin, an unarmed child attempting to walk home from the store, will continue to drive our efforts."