Missouri's governor lifted the curfew for the St. Louis suburb of Ferguson on Monday as National Guard troops were called out after days of violent unrest sparked by the fatal shooting of an unarmed black teenager by a white policeman.
The National Guard deployment is the latest in a series of steps by authorities to end the looting and burning of stores that have punctuated protests and raised questions about race relations in the United States since the shooting death of Michael Brown, 18, more than a week ago.
Governor Jay Nixon, who had declared a state of emergency for the town on Saturday and ordered the streets cleared for a curfew that ran from midnight to 5 a.m., said the National Guard would fall under the supervision of the Missouri Highway Patrol.
But retired local business owner Marshall Tucker said: "It ain't getting no better with the National Guard coming in. That'll be worse. Tonight it's going to get really sticky."
Shortly before nightfall on Monday, police with plastic handcuffs took positions and tried to clear a main thoroughfare where protests have taken place at night, directing crowds into designated protest areas.
"They tell you to stand still, then they tell you to keep walking, then they tell you to stand still," said Mark Stafford, a church pastor from O'Fallon, Missouri.
National Guard troops could be seen walking on the fringes of the gathering, and were keeping a distance from protesters. The Federal Aviation Administration said on Monday it renewed a ban on low-flying civilian aircraft over Ferguson to help law enforcement authorities do their job.
Getty photographer Scott Olson, with cameras around his neck and his hands bound behind him, was led off the street by police. Getty Images said in a statement it stood behind its photographer and was working to secure his release.
President Barack Obama said he told the governor that the National Guard use should be limited and urged healing instead of violence. Attorney General Eric Holder will travel to Ferguson on Wednesday, Obama added.
"While I understand the passions and the anger that arise over the death of Michael Brown, giving into that anger by looting or carrying guns, and even attacking the police only serves to raise tensions and stir chaos. It undermines rather than advancing justice," Obama told a news conference.
The president met with Holder on Monday to discuss the unrest. Holder said more than 40 FBI agents were canvassing Ferguson neighborhoods in an investigation that included federal and local officials.
"Moreover, at my direction, an additional medical examination is being performed on the body of Michael Brown," Holder said. Results of official autopsies by federal authorities and the county are pending.
An autopsy conducted on behalf of Brown's family showed he was shot at least six times, including twice in the head. The path of one bullet indicates the 18-year-old may have been lowering his head in surrender when the fatal shot hit, according to Brown family attorney Daryl Parks.
According to police, the officer involved in the shooting said he fired initially after Brown reached into his police car.
Parks told a news conference one bullet hit Brown in the very top of his head and another shattered his right eye.
"His head was in a downward position," Parks said. "Given those kind of facts, this officer should have been arrested," Parks said.
There were no signs of struggle with the officer and no gunshot residue on the body.
Darren Wilson, 28, the officer who shot Brown as the teenager was walking through a Ferguson residential neighborhood on Aug. 9 with a friend, was put on paid administrative leave and is in hiding.
Edward Magee, a spokesman for the St. Louis County prosecutor's office, said the case could be presented this week to a grand jury, which will decide whether Wilson will be indicted.
Thousands of demonstrators, angry that the police officer was not arrested, have filled the streets. Most if the town's 21,000 residents are black, with many saying the shooting was emblematic of police excesses, charge authorities deny.
According to local police, Brown and a friend were walking down a road when Wilson asked them to move onto the sidewalk. Wilson reported that Brown reached into his patrol car and struggled for his gun when the officer fired the initial shot.
Brown's friend Dorian Johnson, 22, said Wilson had reached out his car window to grab Brown and the teenager was trying to get away. Johnson said Brown held up his hands to surrender but Wilson got out of his car and shot him several times.
The National Bar Association, the country's largest network of black attorneys and judges, filed a lawsuit on Monday against Ferguson and its police department over evidence related to Brown's shooting.
The suit asks the department to preserve all videos, photographs, police logs and investigative reports about the shooting, as well as arrest reports for protesters who were detained in the days and nights that followed.
Looting has left several stores in shambles, with police saying they have been attacked with Molotov cocktails.
Law enforcement officials have been widely criticized for using excessive force.
Two children were treated and released from a hospital for injuries caused on Sunday night by tear gas exposure, the St Louis Children's Hospital said.
U.N. Secretary-General Ban Ki-moon urged U.S. authorities to protect protesters' rights to peaceful assembly.