I'll go ahead and start with one that happened in my own state, Illinois.
Lane Bryant shooting - The Lane Bryant shooting was an incident of mass murder and armed robbery at a Lane Bryant clothing outlet in the Brookside Marketplace in Tinley Park, Illinois, a suburb of Chicago, that occurred on February 2, 2008. The shooting resulted in five deaths and one injury.
Four customers, a part-time employee, and the store manager were taken to the back of the store and shot. Five of the women were killed; the part-time employee was wounded but survived. Police found the victims shortly after receiving an emergency call at 10:45 a.m. The gunman was described as a black man with thick, cornrowed hair and a receding hairline, along with one braid lying over the right side of his face at cheek level and decorated with four light-green beads on the end. Police believe it was a robbery "gone awry."
Info via Wikipedia
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