His death has sparked protests against police brutality in Baton Rouge, and family members and the local NAACP branch called for an independent review outside of the city's police department.
"I have full confidence that this matter will be investigated thoroughly, impartially and professionally," Louisiana Gov. John Bel Edwards said at a news conference Wednesday.
Gov. Edwards, a Democrat, said the investigation into the use of unreasonable or excessive force will be assisted by the U.S. Attorney's Office and the FBI in the state.
The Justice Department confirmed the opening of the case, but declined to comment further.
Hillar Moore III, a district attorney for East Baton Rouge Parish, said he would stand down as the federal investigation looks at whether any laws were broken.
Edwards said that he has "very serious" concerns after watching the cellphone footage, which was "disturbing, to say the least."
At a separate news conference Wednesday, officials identified the officers, both white, as Blane Salamoni, a four-year department veteran, and Howie Lake II, a three-year veteran.
Officials would not detail the "altercation" between the officers and Sterling or whether a Taser was reportedly used, but said police body cameras, dashcam video and any other footage from the scene would be part of the investigation.
Baton Rouge police said in an earlier statement that uniformed officers responded to a call after midnight Tuesday involving a black male in a red shirt who was selling CDs outside of the Triple S Food Mart. Police said the caller claimed Sterling was acting threatening with a gun.
The officers "made contact" with the 5-foot-11 Sterling in the parking lot of the convenience store, and an altercation ensued, police said.
"Sterling was shot during the altercation and died at the scene," the statement said.
It was not clear if both officers shot Sterling or which one fired the fatal shot.
The officers have been placed on administrative leave "per standard procedure," police added.
Sterling died from multiple gunshot wounds to the chest and back, according to East Baton Rouge Coroner Dr. William Clark. He would not immediately confirm reports that Sterling was shot seven times.
The president of the NAACP, Cornell Brooks, called video of the incident hard to watch — but "far harder" to ignore.
"Get on the ground, get on the ground" is heard before two officers confront a man in a red T-shirt. One officer tackles the man, throwing him on the hood of the car and onto the ground. The second officer climbs on and helps hold him down.
One officer appears to shout a warning: "He's got a gun! Gun!"
While the man is on the ground, one officer pulls out his gun. He holds it the back of the man's head or neck, shouting is heard, and then two pops — as the camera quickly cuts away. At least two more pops are heard.
Background voices are heard saying "Oh, my God" and "They shot him?" and "They killed this boy."
"Oh, my God," a woman's voice shrieks.
Sterling is a convicted felon, and wouldn't be permitted to have a gun. But those who knew him said he kept one to protect himself from robbers.
Police officials declined to say whether a gun was found on Sterling.
Edmond Jordan, a Louisiana state representative and Sterling family attorney, said whether or not Sterling had a firearm is irrelevant because, at the moment he was pinned, the video didn't appear to show him wielding a weapon or pulling one out.
Sterling's sister, Mignon Chambers, said something "needs to be done" in wake of the shooting.
"There's no reason for you to handle him the way that you did," she said. "It wasn't right."
Quinyetta McMillon, the mother of Sterling's 15-year-old son, said officers handled the incident "unjustly," and told reporters Wednesday that they killed a man who was "simply trying to earn a living and take care of his children."
"I, for one, will not rest or ... allow him to be swept in the dirt," McMillon said as Sterling's son sobbed behind her.
Sterling had recently been residing in a transitional living center, according to The Advocate newspaper.
Mufleh Alatiyat, an employee of Triple S Food Mart, told The Associated Press that Sterling was generous and said he often gave away CDs or bought food or drinks for other customers.
Some lawmakers said Sterling's family deserves answers for what happened.
State Rep. Ted James called the shooting a "murder," saying in a statement it "has made me question what it really means to be land of the free and home of the brave."
James also demanded an independent investigation and scrutiny of the police department's body-camera policy.
At Wednesday's news conference, officials said there is body camera footage from the officers but Baton Rouge Police Chief Carl Dabadie Jr. said it "may not be as good as we hoped for."
During the altercation, the body cameras became dislodged from the officers, but they remained activated, he added.
State Rep. C. Denise Marcelle, who sponsored the bill to equip Baton Rouge officers with body cameras, said at Wednesday's news conference that she wants police to stop using those body cameras in favor of ones that don't seem to fall off so easily.
Mike McClanahan, of the local NAACP, said at the same news conference that the two officers, who have not been identified, should be arrested and that Dabadie and Baton Rouge Mayor Kip Holden need to step down.
"This is a new day," McClanahan added. "We will not have anybody who allows this type of action to take place."
Both Holden and Dabadie said they would not resign amid the tension over the shooting.
"Like you, I am demanding answers," Dabadie said.
Congressman Cedric Richmond cited "a number of unanswered questions" around the "tragedy" — including the level of force and response of officers after.
"The video footage released today of the shooting of Alton Sterling ... was deeply troubling and has understandably evoked strong emotion and anger in our community," Richmond said in a statement. "I share in this anger and join the community in the pursuit of justice." He called for protests to be conducted "with dignity."
A vigil was planned for Wednesday night outside the convenience store where Sterling died.
Protesters had gathered outside there overnight Tuesday, chanting "black lives matter" and holding signs saying "Honk for justice" as car horns blared.
#AltonSterling was trending on Twitter amid the mounting outrage.
Martin Luther King's youngest daughter, Bernie King, was among those adding her voice.
"May his name and his brutal last breath shake up and transform systems," she wrote on Twitter.
Saturday, January 20 2018 12:26 AM EST2018-01-20 05:26:56 GMT
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