Black smoke billows from fires in the Greenwood district of Tulsa, Okla., during the 1921 Race Massacre. Corbis via Getty Images hide caption toggle caption Corbis via Getty Images National New Research Identifies Possible Mass Graves From 1921 Tulsa Race Massacre December 17, 2019 • "I'm as confident as I can be in the results that this is a very big candidate for something associated with the massacre," a senior researcher at the Oklahoma Archeological Survey said on Monday.