Michael Brown killing: State police to take charge
State police have taken charge of security in Ferguson after nights of violence, said the Missouri governor.
Over the past four nights, heavily armed local police have clashed with protesters angry at the police killing of black teenager Michael Brown.
Governor Jay Nixon announced the change after President Barack Obama urged police not to use "excessive force".
The governor said the violent confrontations with county police made the suburbs resemble a "war zone".
"We're going to have to regain trust," he said.
Missouri Highway Patrol's Captain Ron Johnson, who grew up nearby, has taken charge of the operation.
He lost no time in making his presence felt, escorting a peaceful march through the streets of Ferguson on Thursday evening, shaking hands with protesters.
The tension in Ferguson was sparked by the death of Michael Brown, 18, on Saturday afternoon.
A vigil and a moment of silence in his honour has been scheduled in cities across the US at 19:00 EST (00:00 GMT).
Details about the incident have been disputed but eyewitnesses said the unarmed teenager had his arms raised when he was shot multiple times by a police officer.
Police say there was a struggle and the officer suffered facial injuries.
The authorities have yet to release the officer's name, saying they are worried that his life and that of his family could be in danger.
But this decision has provoked anger from the two-thirds black community of Ferguson against the majority white police force.
The online hacker group Anonymous earlier released what they believed was the name of the police shooter. It was later dismissed as incorrect by police.
On Wednesday night, heavily armed riot police fired tear gas at demonstrators who had ignored an order to disperse.
Several people were arrested, two of them journalists who said they were assaulted before being released.
In a specially convened press conference during his holiday, Mr Obama said there was "no excuse" for police to use excessive force against peaceful protesters.
"Here in the United States of America, police should not be bullying or arresting journalists who are just trying to do their jobs and report to the American people on what they see on the ground," he said.
But Mr Obama also recognised the violence and criminal behaviour police had faced since Mr Brown's killing.
"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.
And Attorney General Eric Holder said the deployment of military equipment and vehicles sent a "conflicting message."
Mr Holder added local Missouri police had an accepted an offer from the justice department for "technical assistance... in order to help conduct crowd control and maintain public safety without relying on unnecessarily extreme displays of force".
Ferguson Police Department Chief Thomas Jackson described the situation as a "powder keg".
He said firebombs were being thrown at police and one officer suffered a broken ankle after being hit by a brick.
"We would like the protesters to stop the violence, we certainly don't want to have any violence," he said.
Of those young black men and women taking to the streets to protest, many say they have no other outlet to show their objection.
"You're going to have to respect the fact we're citizens in this city and you're going to give us equal rights," Michael Brown's neighbour, Howard Bronner, told the BBC.
Mr Obama has promised a full investigation by the US Department of Justice into the teenager's death, and the FBI has launched its own inquiry.