"Three generations of police in this family," Police Commissioner William J. Bratton said of Holder, whose father and grandfather were police officers. "And the latest generation served here with us in the New York City Police Department."

New York Mayor Bill de Blasio added, "We are humbled by Officer Randolph Holder's example, an example of service and courage and sacrifice. Our hearts are heavy. We offer our thoughts and our prayers to his family."

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4. Holder is the fourth New York officer killed in 11 months, Bratton said. Officers Wenjian Liu, 32, and Rafael Ramos, 40, were killed last December after they were ambushed by suspect Ismaaiyl Brinsley, who later killed himself, the New York Times reports. Another officer, Brian Moore, reportedly was killed in May. Demetrius Blackwell, 35, was charged with first-degree murder in the case, according to the Times.

"New York City police officers every day go out and carry themselves like superheroes, but the reality is when we're attacked we bleed, when we bleed we die and when we die we cry," Patrolmen's Benevolent Association President Patrick Lynch said.

>> Click here to read a Facebook post from the New York Police Department