By Lisa Brown and Tim Bryant

A peaceful day of protest and remembrance dissolved into chaos late Sunday after shots were fired. St. Louis County police said an officer was involved in a shooting, but the circumstances were not immediately known.

At least 15 shots rang out about 11:15 p.m. as a standoff continued between police and protesters who had blocked West Florissant Avenue north of Ferguson Avenue.

In a chaotic scene, police officers, reporters and protesters ran for cover. People sprinted across the street and dived behind parked cars.

Ferguson's interim police chief, Andre Anderson, had just finished a television interview saying officers were placed throughout the community to protect businesses, and he was hoping to be patient and allow the protesters to march peacefully.

The law enforcement officers had threatened to arrest protesters who stayed in the street. Protesters by then were estimated at fewer than 100 and were outnumbered by members of the media, observers said.

The violence came exactly one year after the police shooting of Michael Brown. But the day was mostly peaceful with about 1,000 people gathering at the shooting spot in the Canfield Green apartment complex before embarking on a "silent march" with Brown's family members up West Florissant Avenue.

"We came because it's still needed," said Dumine DePorres, who was among a group of 15 people who traveled from Detroit for Ferguson-related events this weekend. "We need to start some conversations that are not just one way, about justice," he said.

The marchers, whose number swelled to more than 1,000 just after noon Sunday, were silent during the 1.5-mile walk up West Florissant Avenue and across Chambers Road to Greater St. Mark Family Church out of respect for Brown, said James Evans Muhammad of Black Educators and Lawyers for Justice.

He said demonstrations planned for Monday will be louder. About 300 people gathered inside the church late Sunday afternoon following the march for a community service.

Riding just ahead of the march in a four-wheeler with Missouri Highway Patrol Capt. Ronald S. Johnson, St. Louis County Police Chief Jon Belmar praised marchers. "Everybody understands we're in this together," Belmar said.

Many marchers held signs, including several that said "Stop killing black children," and "we remember Mike Brown."

During an hourlong event in Brown's memory before the march, the crowd observed 4{ minutes of silence around noon, then counted down 30 seconds before the release of several white doves. About a dozen people, including Brown's father, Michael Brown Sr., spoke about the shooting and the calls for reform that followed. He also thanked his friends and family and others who gathered. "I just want to give my love out to you all," he said.

During the gathering, the mood began as relaxed and chatty, with music played over a loudspeaker, but turned more serious as the program began near a memorial to Brown set in the street on Canfield Drive, a short distance off West Florissant Avenue. Several dozen stuffed animals were arranged in a line as a tribute to Brown, alongside balloons and candles.

One speaker, Yonasda Lonewolf, said: "Mike Brown was murdered here. This was the epicenter of the movement of 'black lives matter.' We still cannot get justice." She added, "It's time for us to not seek justice but to demand justice." Lonewolf is the granddaughter of Minister Louis Farrakhan, leader of the Nation of Islam.

Others included the daughter of Eric Garner, whose killing by New York police provoked protests there.

Another activist, Brittany "Bree" Newsome, who received national attention in June by climbing a flagpole near the South Carolina Capitol to take down a Confederate battle flag, told the crowd: "All I did when I climbed up that pole is remember the courage here in Ferguson."

Several hundred people gathered Sunday night to talk about the role of the black church moving forward at Greater St. Mark Family Church. The Rev. Traci Blackmon told the crowd that there are two purposes for the church. One is to tell the truth, the other is to care for those who cannot care for themselves. "If those things are not happening, you are not the church," she said.

Princeton University professor Cornell West said "the Christian church has been an abysmal failure" when it comes to helping poor, black and working people.

He criticized multiple institutions, including police, public schools and financial institutions.

During a torrential rain storm about 9 p.m. Sunday, several people broke the door on Bowen's Beauty Supply. The cash register was stolen and dumped in the parking lot. About a dozen Missouri State Highway Patrol and police cars responded.

Post-Dispatch reporter Paul Hampel was beaten and robbed while covering the protests Sunday night. He was not seriously injured.

Shortly before Sunday's program on Canfield, the sun broke through an overcast sky, more closely matching conditions of Aug. 9, 2014, when the shooting of Brown, an unarmed black 18-year-old, by white Ferguson Officer Darren Wilson ignited a national backlash over race and policing. Separate investigations by a St. Louis County grand jury and the U.S. Department of Justice found no cause to charge Wilson in Brown's death.

St. Louis Alderman Antonio French, a prominent figure in the protest movement here, said before the program, "It's an opportunity to see how far we have come in the last 365 days." He noted that a large part of the crowd was white.

The toll of heat and humidity on Sunday's crowd was apparent, with many fanning themselves, and one stricken woman lying under the shade of a tree to recover.

A drive-by shooting occurred near a march after Sunday's ceremony but did not appear to be related, according to Jack Webb of the St. Louis County police. A man was wounded in the foot about 1:45 p.m.

A witness told police that seven to nine shots were fired from a passing car. The victim's wound was not believed to be life-threatening.

Shortly before 4 p.m. Sunday, police arrested a man and woman in a green Pontiac that fit the wanted car's description, after a pursuit that started in Hillsdale culminated in St. Louis. A toddler in that car was turned over to family members.

Also Sunday, county police announced charges against Trevion Hopson, 17, in connection with the wounding of a man at a Brown-related gathering in Ferguson about midnight Saturday. The victim, 22, told officers he was hit while standing outside a strip mall on West Florissant.

About the same time that the man was shot, the rear window of an unmarked Florissant police vehicle was shattered as it traveled south on West Florissant in the same area.

County officers quickly arrested Hopson. Prosecutors charged him Sunday with unlawful use of a weapon and resisting arrest. Hopson, of the 8700 block of Boyce Place in Jennings, was held in lieu of $100,000 cash-only bail.

Officials said Hopson, who attended the protest for the anniversary, carried a firearm in his backpack, fired at a "specific target" and also fired several shots into the crowd as people ran, then replaced the weapon in the backpack and ran. Officers chased him down and recovered a gun and backpack.

(Paul Hampel, Walker Moskop, Lisa Brown and Tim Bryant of the Post-Dispatch contributed to this report.)

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