Missouri state police were Thursday ordered to replace local forces in a US town rocked by protests over the shooting of an unarmed black teenager, following complaints led by President Barack Obama.
State Governor Jay Nixon said the decision had been taken after the St. Louis suburb of Ferguson was left looking "like a war zone" after rioting triggered by the shooting of 18-year-old Michael Brown.
Police in Ferguson have attracted widespread criticism for their response to the unrest amid allegations of police racism.
The county police response to daily, and nightly, protests since the shooting has been aggressive, with rifle-toting police in military-style fatigues and body armor deployed to crush dissent.
"Lately it looks like a war zone and that is not acceptable," Nixon said of Ferguson, appointing a local African-American officer, Captain Ron Johnson, to take charge, instead of the St. Louis County police who had led the crackdown.
Johnson works for the Missouri Highway Patrol, which answers to the state government. He said police would show respect to the citizens as they try to restore calm.
"I grew up here and this is currently my community and my home. It means a lot to me personally that we break this cycle of violence and build trust, and show the utmost respect," he said, adding he understands "the anger and fear that the citizens of Ferguson are feeling."
The governor, however, did not cede to one key demand of the protesters. Control of the investigation into the police shooting of Brown will remain in the hands of the St Louis County force.
The US Department of Justice has already announced a separate federal investigation into whether the mainly white force had committed a civil rights violation in the majority black town.
- 'Peace and calm' -
The police crackdown in Ferguson, in which authorities fired tear gas, rubber bullets and sound bombs and arrested reporters, has sparked numerous complaints.
Many are also frustrated at the lack of information provided about the investigation, including withholding the name of the officer who shot Brown and even how many shots were fired.
President Barack Obama called for "peace and calm" Thursday, adding authorities had a responsibility to be "open and transparent"
"Now is the time for peace and calm on the streets of Ferguson," Obama told reporters. "Now is the time for an open and transparent process to see that justice is done."
"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 added.
"There's 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."
His attorney general, Eric Holder, spoke even more candidly, saying in a statement, "the law enforcement response to these demonstrations must seek to reduce tensions, not heighten them."
Amid Wednesday night's unrest, police also arrested, and later released without charge, two journalists covering the events.
Wesley Lowery, a Washington Post political reporter, and Ryan Reilly, who works for the Huffington Post, were detained in a McDonald's after police entered the eatery and ordered people to leave, the pair wrote on Twitter.
Obama referenced the incident, warning: "Here in the United States of America, police should not be bullying or arresting journalists who were just trying to do their jobs and report to the American people on what they see on the ground."
- 'We have to get answers' -
As day broke, the Brown family's attorney had also appealed for calm and urged federal authorities to carry out an independent autopsy of their son's body.
"There is nothing Michael Brown could have done to justify him being executed in broad daylight, and this is the worst police shooting I have ever seen," Benjamin Crump told CNN.
"We have to get answers and it has to be transparent and that's why we're calling on the Justice Department and the attorney general to do an independent autopsy."
Obama, in his remarks, said he had already tasked the FBI to independently probe Brown's death along with local officials on the ground.
He added that he had made clear to Attorney General Eric Holder "that we should do what is necessary to determine exactly what happened and to see that justice is done."