Following the death of three law enforcement officers in Baton Rouge, La., on Sunday, President Obama said that "attacks on police are an attack on all of us."

Three officers were killed and three others were wounded in an encounter that began shortly before 9 a.m. Sunday. Louisiana law enforcement said they believe the gunman who shot at officers was killed at the scene. A law enforcement source confirmed to NPR the identity of the shooter as Gavin Eugene Long. The 29-year-old black man was a former Marine who served from August 2008 to August 2010.

"Nothing justifies violence against law enforcement," Obama said Sunday afternoon, speaking at the White House. "Our hearts go out to the families who are grieving," he said, adding that "this has happened far too often."

The shooting comes just five days after Obama spoke at the memorial service in Dallas for five police officers murdered by a gunman on July 7. The Dallas shooting followed two widely publicized shootings of African-American men by police, in Baton Rouge and in a suburb of Minneapolis.

Echoing his comments in Dallas calling for unity in the face of racially charged shootings, the president called for Americans to "make sure our best selves are reflected across America," and "focus on words and actions that can unite this country."

Obama asked for citizens to reflect the actions of people in Dallas, many of whom expressed their support for police following the city's violence. The president offered "respect and gratitude" to police for their work.

He vowed that "justice will be done." As of Sunday afternoon, Obama said authorities did not know the motivation of the killer.

Baton Rouge has been the site of recent protests ignited by the shooting death of 37-year-old Alton Sterling at the hands of police earlier this month. A video of the incident captured by witnesses shows Sterling on the ground with two officers kneeling over him.

The incident and other shootings of African-American men by police across the country have inspired continued nationwide protests since 2014 and the Black Lives Matter movement. Critics accuse the movement of inspiring violence toward law enforcement, a charge leaders have rejected.

As the Two-Way reported last week, Obama has acknowledged that racial prejudice in institutions like law enforcement still exists:

"We also know that centuries of racial discrimination — of slavery and subjugation and Jim Crow — they didn't simply vanish with the end of lawful segregation," he said.

"America, we know that bias remains. We know it," the president continued. "None of us is entirely innocent. No institution is entirely immune."

On Sunday, he said the "best way to honor the sacrifice" of fallen police officers is to set an example for children.

"It's up to all of us to make sure we are part of the solution," the president said, "and not part of the problem."

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