Their deaths have brought the spotlight back on a region where the shooting death of Alton Sterling at the hands of police started what has been two weeks of national turmoil.
"We as a nation have to be loud and clear that nothing justifies violence against law enforcement," President Obama said after Sunday's attack.
"Attacks on police are an attack on all of us, and the rule of law that makes society possible."
After the incident, police across the country are taking numerous precautions.
The New York Police Department is doubling up all foot patrols and security posts, reveals a memo, reports CNN. Officers have also been instructed to take all meals and personal breaks in pairs.
Although Baton Rouge is "hundreds of miles away from Boston, the pain and suffering caused by the loss of these officers in the line of duty is felt deeply by the men and women of the BPD," Boston Police Commissioner William Evans said.
"This all too common trend we are seeing of violence against law enforcement officers who are out there each day serving and protecting neighborhoods across the country is alarming and disheartening."
President Obama said, "Only we can prove, through words and through deeds, that we will not be divided."
"And we're going to have to keep on doing it again and again and again. That's how this country gets united."