Police on alert across America after murder of NYPD officers

The murders of New York City Police Department officers Rafael Ramos and Wenjian Liu in Brooklyn Saturday heightened fears about the safety of law enforcement officials nationwide, though there is no evidence any threats are imminent.

Fox News reports officers in other parts of the country are being encouraged to wear bulletproof vests, avoid inflammatory statements on social media, not to patrol alone and only to make arrests if they have to.

The gunman, 28-year-old Ismaaiyl Brinsley, had vowed in an Instagram post to put "wings on pigs" as retaliation for the slayings of black men at the hands of white police. The shooter was black and the officers were Hispanic and Asian.

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