You are referring to the Greenwood District Massacre, also known as the Tulsa Race Riot. It took place in 1921 when a white mob attacked residents, homes and businesses in the predominantly black neighborhood of Greenwood in Tulsa, Oklahoma. The incident was one of the most severe episodes of racial violence in U.S. history, but was largely overlooked for decades.
In 2021, President Joe Biden announced plans to acknowledge the incident by declaring the site a national monument. This would be a significant step in recognizing the history of racial violence in America, as it would be the first time such a site received this level of recognition.