Three officers are dead and three others wounded after the shooting less than 1 mile from Baton Rouge police headquarters. Police said they have killed the suspect involved in the shootout.
"We are TRYING to fight ISIS, and now our own people are killing our police," Trump posted on Twitter. "Our country is divided and out of control. The world is watching."
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Democratic presidential candidate Hillary Clinton called the shooting an attack on us all.
"There is no justification for violence, for hate, for attacks on men and women who put their lives on the line every day in service of our families and communities," Clinton said in a statement.
Libartarian presidential candidate Gov. Gary Johnson called the attack senseless.
President Barack Obama urged Americans to tamp down inflammatory words and actions as a violent summer collides with the nation's heated presidential campaign.
"We as a nation have to be loud and clear that nothing justifies attacks on law enforcement," Obama said from the White House. "Every one right now focus on words and actions that can unite this country rather than divide it further."
Louisiana Gov. John Bel Edwards condemned the attacks in a statement released Sunday.
"This is an unspeakable and unjustified attack on all of us at a time when we need unity and healing," Edwards said.