Police Departments Across The Country On High Alert After NYC Cop Murders. Eric Garner's Family Urges Non Violence

RadioOnFire.com - NEW YORK (Associated Press) — Big-city police departments and union leaders around the country are warning the rank and file to wear bulletproof vests and avoid making inflammatory posts on social media in the days after a man ambushed two officers and shot them to death inside their patrol car.

The slayings of Officers Rafael Ramos and Wenjian Liu on Saturday afternoon in Brooklyn heightened fears about the safety of law enforcement officials nationwide, though authorities haven't said if they believe any threats are imminent. 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.

Rafael Ramos (left) and Wenjian Liu

Brinsley was black; the slain New York Police Department officers were Hispanic and Asian.

Investigators are trying to determine if Brinsley had taken part in any protests over the deaths of Michael Brown and Eric Garner, whose names he invoked in his online threat, or simply latched onto the cause for the final act in a violent rampage.

Eric Garner (left) and Michael Brown

The slayings come at a tense time as police nationwide are being criticized following Garner's death in a New York officer's chokehold and Brown's fatal shooting in Ferguson, Missouri. Protests erupted in recent weeks after grand juries declined to charge the officers involved.

After the officers' killings, a union-generated message at the 35,000-officer NYPD warned officers that they should respond to every radio call with two cars — "no matter what the opinion of the patrol supervisor" — and not make arrests "unless absolutely necessary." The president of the detectives' union told members in a letter to work in threes when out on the street, wear bulletproof vests and keep aware of their surroundings.

Another directive warned officers in Newark, New Jersey, not to patrol alone and to avoid people looking for confrontations. At the same time, a memo from an NYPD chief asked officers to limit their comments "via all venues, including social media, to expressions of sorrow and condolence."