DAVID A. LIEB
Associated Press

FERGUSON, Mo. (AP) — One person was shot and seven people were arrested early Sunday morning as police used smoke and tear gas to impose a curfew in a St. Louis suburb where a black teen walking down the street had been shot by a white police officer.

Missouri State Highway Patrol Capt. Ron Johnson said during a news conference that police are still seeking the person who shot the critically wounded victim and defended his department’s strong strategic response that came after a midnight to 5 a.m. curfew took hold in Ferguson, Missouri. Johnson said the strong police response was precipitated by two events.

Johnson said concerns about people who’d broken into a barbecue restaurant and taken position on the roof overlooking approaching police was one strategic concern. He said another involved a man who flashed a handgun and appeared in the middle of the street as armored vehicles approached the crowd of protesters.

Johnson said someone also fired at a patrol car, but no officers were injured.

Hundreds of other protesters left peacefully before the curfew took effect in Ferguson, where 18-year-old Michael Brown was fatally shot on Aug. 9. The shooting has prompted protests, unrest and claims of civil rights violations.

But remaining protesters — chanting “No justice! No curfew!” — refused to leave the area. As five armored tactical vehicles approached the crowd, officers spoke through a loudspeaker: “You are in violation of a state-imposed curfew. You must disperse immediately. Failure to comply, may result in arrest.”

As officers put on gas masks, a chant from the distant crowd emerged: “We have the right to assemble peacefully.”

A moment later, police began firing canisters into the crowd of protesters.

Highway Patrol Spokesman Lt. John Hotz initially said police only used smoke, but later told The Associated Press that they also fired tear gas canisters. He said of police efforts: “Obviously, we’re trying to give them every opportunity to comply with the curfew.”

Jayson Ross, who was leading the protesters toward police before the canisters were fired, said: “They got guns. We got guns. We are ready.”

The unrest between police and protesters came after Gov. Jay Nixon on Saturday declared a state of emergency in Ferguson.

Nixon’s curfew announcement came after tensions again flared in Ferguson late Friday night. Earlier that day, local police identified the officer who shot Brown as Darren Wilson and released documents and video footage alleging that Brown had robbed a convenience store just before he was shot. Police said Wilson was unaware Brown was a suspect when he encountered him walking in the street with a friend.

As the curfew approached late Saturday night, New Black Panther Party leader Malik Shabazz roamed the street with a bullhorn, encouraging people to leave for their own safety. Many appeared to follow his suggestion.

“C’mon you all, let’s roll out,” Shabazz said through his bullhorn. “Let’s roll out of here, get some rest and come back tomorrow.”

Crowds that were in the hundreds prior to the curfew had dwindled significantly in the final hour.

Keyon Watkins, a 26-year-old computer science worker from St. Louis, said on Saturday that if many others stayed in the street, he would join them.

“All of this is just building up — pent-up aggression by being mistreated on a daily basis,” Watkins said.

In announcing the curfew, Nixon said that though many protesters were making themselves heard peacefully, the state would not allow looters to endanger the community.

“I am committed to making sure the forces of peace and justice prevail,” Nixon said during a press conference at a church that was interrupted repeatedly by people objecting to the curfew and demanding that the officer who shot Brown be charged with murder.

“We must first have and maintain peace. This is a test. The eyes of the world are watching,” Nixon said. “We cannot allow the ill will of the few to undermine the good will of the many.”

State statute gives the governor broad powers when he declares a state of emergency, but he hasn’t indicated that he plans to do anything other than imposing the curfew and empowering the state highway patrol to enforce it.

Meanwhile, Nixon said the U.S. Department of Justice is beefing up its civil rights investigation of the shooting.

Missouri State Highway Patrol Capt. Ron Johnson, who is in charge of security in Ferguson, said 40 FBI agents were going door-to-door in the neighborhood starting Saturday, talking to people who might have seen or have information about the shooting.

Johnson on Saturday said police would not enforce the curfew with armored trucks and tear gas but would communicate with protesters and give them ample opportunity to leave. Local officers faced strong criticism earlier in the week for their use of tear gas and rubber bullets against protesters. Johnson said one tear gas canister was deployed Friday night after the group of rioters became unruly and several officers got trapped and injured.

Brown’s death had already ignited several days of clashes with furious protesters. Tensions eased Thursday after Nixon turned oversight of the protests over to the Missouri Highway Patrol. Gone were the police in riot gear and armored vehicles, replaced by the new patrol commander who personally walked through the streets with demonstrators. But Friday night marked a resurgence of unrest.

On Saturday, some residents said it appeared the violent acts were being committed by people who came from other suburbs or states.

“Who would burn down their own backyard?” asked Rebecca McCloud, a local who works with the Sonshine Baptist Church in St. Louis. “These people aren’t from here. They came to burn down our city and leave.”

Wilson, the officer who shot Brown, is a six-year police veteran who had no previous complaints against him, the local police chief has said.

The Ferguson Police Department has refused to say anything about Wilson’s whereabouts, and Associated Press reporters were unable to contact him at any addresses or phone numbers listed under that name in the St. Louis area.

Wilson has been on paid administrative leave since the shooting. St. Louis County prosecutor Bob McCulloch said it could be weeks before the investigation wraps up.

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Associated Press writer Nigel Duara contributed to this report.

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