FERGUSON, Missouri (CNN) -- State troopers are taking over security in this St. Louis suburb after days of clashes between local police and protesters.
Gov. Jay Nixon said he decided to put the Missouri State Highway Patrol in charge of security because "at this particular point, the attitudes weren't improving, and the blocks towards expression appeared to be a flashpoint."
Lately, the community of Ferguson, which has been the scene of demonstrations and a strong police response in the wake of a weekend police shooting that left teenager Michael Brown dead, has looked "more like a war zone, and it's not acceptable," Nixon said.
Now, authorities -- who've faced accusations that they've used excessive force in response to demonstrations -- will be taking a different tack in an effort to calm tensions, officials said Thursday.
"We're all about making sure that we allow peaceful and appropriate protests, that we use force only when necessary, that we step back a little bit and let some of the energy be felt in this region, appropriately," Nixon said
Chosen by the state's governor to head up the new security operation, Missouri State Highway Patrol Capt. Ron Johnson said he planned to meet with protesters Thursday.
"We are going to have a different approach and have the approach that we're in this together," he said.
Police chief: City is a 'powder keg'
Earlier Thursday, Ferguson's police chief described the city as a "powder keg."
"The whole situation is not good at this point," Chief Thomas Jackson said a day after clashes in which police fired smoke bombs, tear gas and rubber pellets at protesters who he said had thrown firebombs at police and engaged in gunfire.
Jackson said police would talk about changing "not only the tactics but also the appearance" of law enforcement.
U.S. Justice Department officials have also offered to assist local authorities control crowds "without relying on unnecessarily extreme displays of force," Attorney General Eric Holder said in a statement Thursday. The offer has been accepted, he said.
Jackson said protesters also have to do their share by remaining peaceful.
"We need everybody to tone it down," he said.
Crowds of protesters gathering Thursday evening were peaceful.
Rep. Emanuel Cleaver, a Missouri congressman, said he expects the calm to continue now that police are changing their tactics.
"When you get the military equipment out of the way, I think it gives the protesters the feeling that we can now protest peacefully, and there's no threat hanging over us," he said.
Governor: 'This has clearly touched a nerve'
Ferguson has been the scene of protests since Saturday, when a police officer shot and killed Brown, who was unarmed. Police say he was trying to grab the officer's gun. Witnesses say the 18-year-old was holding his hands in the air when he was fatally shot.
Protesters are angry that police have not released the name of the officer involved in the shooting, and they worry that a cover-up is in effect. St. Louis County police and federal investigators are looking into Brown's death. No charges have been filed.
Although locals say race relations have long been troubled between the city's mostly African-American population and the mostly white police force, anger spilled out after Brown's death, resulting in protests, violence, looting and fires.
Brown's death and demonstrations over the case have resonated far beyond that city, Nixon said Thursday.
"These are deep and existing problems not only in Missouri but in America, and this has clearly touched a nerve," he said.
President Barack Obama also spoke out.
"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."
Their comments came after a night in which heavily armed police and protesters clashed, two reporters were briefly detained and an Al Jazeera America camera crew complained that police shot tear gas at them.
After ordering protesters and reporters to turn off their cameras, police fired smoke bombs, tear gas and rubber bullets at protesters after some threw objects at them Wednesday, according to media accounts. CNN crews have not been ordered to turn off their cameras during the protests.
Twelve people were arrested -- including the two reporters, Jackson said. Two officers were injured, including one whose ankle was broken when a brick was thrown at him.
'Just in shock'
On Wednesday, the American Civil Liberties Union of Missouri filed a lawsuit seeking the release of the officer's name under the state's open records law.
It's unclear whether the suit will succeed. Missouri law provides a specific exemption barring the release of records that authorities conclude are "likely to pose a clear and present danger" to victims, witnesses or others.
Officials say police officers, and others in the administration and police force, have been subjected to death threats.
On Thursday, the shadowy activist group Anonymous published the name of the officer it believes responsible for the shooting. Earlier, the group claimed to have hacked the city servers and obtained dispatch recordings and other information.
Jackson later said the group had the wrong officer. CNN is not reporting the name.
Attorney Benjamin Crump, who's representing Brown's family, said they're frustrated with the lack of information from police.
"Like all the people in that community and many people around the country, they're just in shock that this could happen to an unarmed teenager in broad daylight," he told CNN. "It makes no sense, and they feel there's no way it could be justified."
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