Americans have held demonstrations across the country to protest the killing of an African-American teenager who was shot dead by a white police officer in the state of Missouri last week.
On Saturday, 18-year-old Michael Brown was shot multiple times and killed by police in the St. Louis suburb of Ferguson, a predominantly black town. Since then, protests over the fatal shooting have been held in St. Louis every night.
On Thursday, tens of thousands of people staged massive rallies to protest racial discrimination against African-Americans and other communities in more than 100 cities and towns, including Washington, New York, Boston, St. Louis and Philadelphia.
In New York, a massive crowd overwhelmed a police presence in Union Square park, forcing officers to close one of Manhattan's major thoroughfares. Police arrested a number of protesters.
In St. Louis, thousands of people peacefully gathered to protest the shooting.
"I have two grandchildren, and I want them to be able to walk the streets safely without the police shooting them," said Debbie Ray, who attended the protest in St. Louis.
"There doesn't seem any reason in the US for rifles to be aimed at people in the streets," Ray added. "Will they have firehoses and dogs in the street next?"
"We want to stand in an effort of love and support and organize community support for how we can mobilize our anger and our upset and our disappointment," said Renee Chapman, an organizer of the vigil at Marshall Park in Charlotte, North Carolina.
Protesters criticized the police for killing the unarmed black teenager and called for an end to the racial killings.
Meanwhile, the security of the city of Ferguson, where the deadly shooting happened, has been handed over to state police.
The decision has been taken after nights of violent clashes there. Local police have been criticized for dealing harshly with protesters.
Earlier on Thursday, US President Barack Obama called for "peace and calm" and urged police to respect protesters. He also demanded an investigation into the killing.