NEW YORK (AP) — New York City Police Commissioner Bill Bratton says an officer and his partner were "assassinated" last week in an ambush because they wore a uniform.

Bratton spoke to more than 20,000 officers from across the country who gathered Saturday at the funeral of Officer Rafael Ramos.

Bratton is set to appear Sunday on CBS' "Face the Nation."

Vice President Joe Biden said the murders of Ramos and his partner, Officer Wenjian Liu, "touched the soul of an entire nation."

Police union officials have criticized Mayor Bill de Blasio saying his support of police reform protests contributed to a climate of mistrust that preceded the killings.

At the funeral, a few hundred officers outside the church turned their backs on giant screens displaying de Blasio's eulogy.

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