The black US marine corps veteran who shot dead three police officers in Louisiana’s capital planned his attack for days and then assassinated the men, US police said on Monday, as the country reeled from the latest deadly shooting involving police and black Americans.
One of the three officers wounded in Sunday's shootings was hit in the head and stomach and was fighting for his life, police said at a news conference in Baton Rouge.
The city has been the scene of repeated protests against police violence after the fatal shooting by officers of Alton Sterling, a black man, outside a convenience store on July 5th.
"There is no doubt whatsoever that these officers were intentionally targeted and assassinated," Louisiana state police Supt Col Mike Edmonson said at the news conference.
“It was a calculated act against those who work to protect this community every single day.”
Edmonson said “the most compelling piece of evidence is the video” of the shooting.
Three guns were recovered from the scene and much was learned about the attack from the gunman’s social media footprint, Edmonson told reporters.
He said the gunman “had been in our community for several days”.
The gunman has been identified as Gavin Long, a 29-year-old from Kansas City, Missouri, who served in the Marines for five years, including a 2008 deployment in the Iraq War.
Long, dressed in black and armed with a rifle, was shot dead on Sunday morning in a gunfight with police.
Racial tensions in the US has been especially high since a black former US army reserve soldier fatally shot five Dallas police officers who were patrolling a protest over the police shootings of Sterling and another black man in Minnesota.
It has emerged that the Baton Rouge gunman said he wanted to change his name from Gavin Eugene Long to Cosmo Ausar Setepenra in May 2015, according to Jackson County, Missouri, public records.
However, court officials said he never completed the process of legally changing his name.
A website, social media accounts and YouTube videos that appeared tied to Long included complaints about police treatment of black people and praise for killings of the Dallas policemen.
Louisiana governor John Bel Edwards told Monday's news conference that Long "came to do harm" and he called the shooting "pure, unadulterated evil".
Police said a member of the Swat team that responded to the scene killed Long with a shot from 100 yards away.
East Baton Rouge parish sheriff Sid Gautreaux said he had "no doubt" that Long would have killed additional officers if not for that shot.
Long also affiliated himself with the Washitaw Nation, an black American offshoot of the Sovereign Citizen Movement, a group whose members view the federal government as illegitimate.
The dead officers in Baton Rouge have been identified as Montrell Jackson (32), Matthew Gerald (41) and Brad Garafola (45).
Two other officers were treated for their wounds in hospital and released.
At the B Quick gas station where the shootings occurred, people left flowers and balloons in memory of the slain officers.
"I just want us to have peace and drive down the road and not feel like we have to duck our heads and look around and see if someone's going to be on top of a roof," said Pam Collins, a resident of the Baton Rouge suburb of Prairieville, who brought three shiny balloons to honor the officers.
Presumptive Democratic presidential nominee Hillary Clinton, in a speech to the NAACP civil rights group in Cincinnati, said she would bring the "full weight of the law to bear" against police killers, but added that here is "another hard truth at the heart of this complex matter: Many African-Americans fear the police".
She said the police shootings of Sterling in Baton Rouge and Philando Castile in Minnesota “drove home how urgently we need to make reforms to policing and criminal justice [and] how we cannot rest until we root out implicit bias and stop the killings of African-Americans”.
Her Republican rival for the presidency, Donald Trump, tweeted that "our country is a divided crime scene" and called for stronger leadership on law and order issues.
Louisiana’s capital has a long history of distrust between black residents and law enforcement.
For many in Baton Rouge, the police have been viewed as overly aggressive and unrepresentative of a city where more than half the 230,000 residents are black.