known as the tulsa race massacre, a deadly and coordinated attack on the prosperous african-american neighborhood in tulsa, oklahoma, also called black wall street. it is one of the worst incidents of racial violence in u.s. history, and it was swept under the rug for decades and decades. our friend and colleague harry smith traveled to tulsa for a revealing look back. reporter: on june 1, 1921, 9-year-old el doris was awakened by her mother. what her mother said next, she never forgot. she said we have to go out, get out. she said, the white people are killing the other people. reporter: el dorous grew up in the greenwood area of tulsa, a buoyant, bustling community of some 10,000 african-americans. there were schools, churches, stores, theaters and a hospital. it was a place where for