US celebrities called for a boycott to take place Friday -- one of the busiest US shopping days -- to protest a grand jury's decision not to prosecute a police officer who fatally shot a black teen.
A number of well-known figures, among them hip-hop mogul Russell Simmons, have signed onto the action, under the Twitter hashtags #NotOneDime and #BlackoutBlackFriday.
"We have the power to change our nation. Stand up with @UnitedBlackout on #BlackoutBlackFriday," tweeted one of the supporters, actress Kat Graham, who stars in TV series "The Vampire Diaries."
Also backing the campaign was TV star Jesse Williams, while journalist Soledad O'Brien retweeted a message with the hashtag #NotOneDime.
"No Just, No Profit. Corporate/public power only speaks $. So let's talk to 'em," Williams tweeted, along with a link to a video compilation of police brutality.
Black Friday is a day of deep commercial discounts and frenzied shopping which takes place each year after the Thursday Thanksgiving holiday in the United States.
The planned campaign calls for a one-day moratorium on spending to protest what it calls "staggering" human rights violations in the United States, including police brutality.
The boycott was prompted by widespread outrage after a grand jury on Monday failed to indict a white police officer in Ferguson, Missouri who shot and killed black 18-year-old Michael Brown in August.
Protests erupted across the US after the decision.
America's 43 million black citizens will hold about $1.1 trillion in purchasing power by 2015, a Nielsen study said.