Handout shows a bullet hole in a window of the Dallas police headquarters in Dallas, Texas

Handout shows a bullet hole in a window of the Dallas police headquarters in Dallas, Texas

A bullet hole is seen in a window of the Dallas police headquarters in Dallas, Texas, in this handout photo released by the Dallas Police Department on June 13, 2015. Shots were fired from what was described as an armored van in an attack on Dallas Police headquarters early on Saturday, police said, and an explosive device was found outside the building. REUTERS/Dallas Police Department/Handout via Reuters

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