Daniel Holtzclaw (center) listens as Oklahoma County assistant district attorney Gayland Gieger (right) speaks during Holtzclaw's sentencing hearing in Oklahoma City, Thursday. Holtzclaw, a former Oklahoma City police officer, was convicted of raping and sexually victimizing several women on his beat. At left is defense attorney Scott Adams. Sue Ogrocki/AP hide caption

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Fired police officer Daniel Holtzclaw cries as guilty verdicts are read in an Oklahoma City court Thursday. Holtzclaw could face life in prison when he's sentenced for rape and other charges next month. Sue Ogrocki/AP hide caption

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Keepsakes of Airman 1st Class Lakesha Levy fill her mother's bungalow in New Orleans. Levy and five other military service members died in the Oklahoma City bombing. Jesse Hardman/WWNO hide caption

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An untouched chalkboard from 1917 was found behind a classroom wall at Emerson High School in Oklahoma City. Jacob McCleland/KGOU hide caption

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A general view of downtown Oklahoma City as basketball fans gather outside Oklahoma City Arena. The once run-down area has undergone a major transformation over the past 20 years. Ronald Martinez/Getty Images hide caption

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Spectators bow their heads during a moment of silence during a ceremony to commemorate the 20th anniversary of the Oklahoma City bombing at the Oklahoma City National Memorial, on Sunday. Sue Ogrocki/AP hide caption

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Phuong Nguyen, 55, and her son, Chris, who survived the bombing of the Alfred P. Murrah Federal Building in Oklahoma City on April 19, 1995. StoryCorps hide caption

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Aid groups are mobilizing relief efforts to help victims of the storm. Here, Candice Lopez, left, and Stephanie Davis help clean debris from Thelma Cox's mobile home near Shawnee, Okla., after it was destroyed Monday. Brett Deering/Getty Images hide caption

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Oklahoma City Bombing: The Albert P. Murrah Federal Building shows the devastation caused by a fuel and fertilizer truck bomb on April 19, 1995. The blast killed 168 people and injured more than 500. Bob Daemmrich/AFP/Getty Images hide caption

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