FERGUSON, Missouri (CNN) — Now we have a name.
Darren Wilson is the police officer who shot and killed Michael Brown in Ferguson, Missouri, police Chief Thomas Jackson told reporters Friday.
He is a 6-year veteran with no disciplinary issues, Jackson said, declining to answer any questions about the officer.
However, before naming him, Jackson spoke to CNN's Don Lemon and said the officer was "devastated" by what had happened.
"This is his community," Jackson said. "He never wanted any of this to happen."
The release of Wilson's name satisfies a key demand of protesters and critics of the handling of the case by the suburban St. Louis police department and St. Louis County investigators handling the probe.
Brown, an African-American teen, was shot to death Saturday. Police have said the shooting occurred during a struggle for the officer's gun. Witnesses have said Brown's arms were raised when he was shot.
After days of sometimes violent protests, the Missouri State Highway Patrol took over security for the protests.
Gone were the military gear and vehicles, the stun grenades, plastic pellets and tear gas police deployed on previous nights. So were the Molotov cocktails, sounds of gunfire and strife from protesters who had wandered among peaceful demonstrators.
The crowds swelled and became more diverse Thursday; their chants for justice accompanied a concert of honking car horns, and though their cause was somber, their mood was buoyant.
Despite the celebrated change in tone after his department stepped back, Jackson said Friday he is not going to resign, as some critics have suggested he do.
"I'm not going anywhere. I'm going to stay and see this through," he said.
Highway patrol Capt. Ron Johnson is now in charge, at the request of Missouri Gov. Jay Nixon.
"We have a different approach that we're using this evening," he told CNN's Don Lemon. Smiling instead of scowling is key. "I've smiled more today than I have in the past few days."
Maj. Ronnie Robinson from the St. Louis City Police is working with Johnson. He underlined the importance of dialogue with residents. "We feel the pain in the community," he said. They can protest 24 hours, if they want to.
He also insisted there will be law and order. No looting, no vandalizing. State troopers will protect small businesses, he said. And protesters may not block the streets.
Despite the new tone by authorities, some protesters said they were prepared for police aggression.
"Gas me, shoot me, I will stand my ground," one sign read.
Antonio French, a St. Louis alderman who was arrested at a demonstration in Ferguson on Wednesday, said he's noticed the new tone.
"Really, it has been the police presence, the heavy-handed presence, which has escalated the situation, and I think led to the violence each night. And so it's good to see this new approach," he said.
Ferguson's police department has been criticized for a lack of ethnic diversity. The St. Louis suburb's population is two-thirds African-American. Of the police force's 53 officers, only six are African-American.
An eyewitness has said that the officer who shot Brown was Caucasian.
Johnson and Robinson are African-American. Though he believes in ethnic diversity and would like to see more in Ferguson's police force, Robinson did not peg it to skin color but to a person's ability to understand people's culture and communicate with them.
"You've got to give respect to get respect," he said.
Authorities have said that the change of appearance of the police force was intentional.
As Robinson spoke, a group of young Caucasian men behind him held up a sign calling for justice for Brown.
The city was a "powder keg," Jackson said earlier Thursday, before the change of guard in security arrangements, which the U.S. Justice Department had influenced. Attorney General Eric Holder said Thursday that local authorities had accepted the department's help.
Upset residents gathered to protest Brown's killing as soon as his body lay in the street Saturday.
No one has disputed that Brown was unarmed. But police say he tried to grab the officer's gun, something two witnesses dispute. They say the officer fired on the 18-year-old as he tried to distance himself and raised his hands into the air.
Demonstrations have continued since, turning into a ruckus after nightfall, and violence has broken out. Police have detained dozens, including two journalists.
President Barack Obama on Thursday called for peace from all sides.
"There is never an excuse for violence against police or for those who would use this tragedy as a cover for vandalism or looting," he said. "There is also no excuse for police to use excessive force against peaceful protests or to throw protesters in jail for lawfully exercising their First Amendment rights."
Brown's killing has gained attention around the world and moved people to protest in other U.S. cities Thursday. In Los Angeles and in New York, hundreds gathered to demand justice for Brown.
The Los Angeles protests included commemoration for Ezell Ford, an African-American youth recently killed there. In New York, police formed a line to halt the march, CNN affiliate WABC reported.
They told the crowd to disperse and arrested a few people.
CNN's Ben Brumfield reported and wrote from Atlanta, and Ana Cabrera reported from Ferguson. CNN's Michael Pearson, Don Lemon and Catherine E. Shoichet contributed to this report.
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