There were high hopes that the nightly protests in Ferguson would end peacefully for a change Tuesday. That promise held out for most of the evening -- until a water bottle flew at police.
By that time, most protesters had cleared out. Journalists outnumbered those who remained.
Officers put on helmets and shields, lined up on in front of some businesses and demanded a small crowd there clear out.
But when the bottle flew, officers broke into a sprint, chasing after young men.
This prompted a handful of agitated protesters to toss more bottles, glass and plastic.
Missouri State Highway Patrol Capt. Ron Johnson, who's tasked with maintaining peace, told reporters that "criminals" had thrown urine on police.
After the chase, number of riot police ballooned. Officers brought out K-9 dogs, and one policeman used pepper spray on some in the crowd.
Protesters locked hands in front of a police line, and some urged the crowd to remain peaceful.
Johnson credited them for preventing further escalation.
Police arrested 47 people, Johnson said, including a car of people driving by, who were armed.
"We identified a vehicle that made threats to shoot an officer," he said.
Started out peaceful
And so it went in the St. Louis suburb, which has been a tinderbox of racial tension since Michael Brown, an unarmed 18-year-old African-American, was shot by a white police officer, Darren Wilson, on August 9. A public funeral for Brown is planned for Monday.
For most of Tuesday night, the streets had been calm. A much smaller crowd than evenings past milled about, holding signs and chanting.
A few hundred people walked up and down a small area. "Hands up! Don't shoot" was their mantra, as it has been every night.
But many of the demonstrators added a second chant: "We protesters, we don't loot."
Jameila White from St. Louis County walked a mile to hand out free water to protesters.
"We pooled together as a community to bring this," she said, pointing to three Styrofoam coolers of bottles water on ice. "So, we can stay energized and keep walking because they're saying if we stand still we're going to get locked up."
White, who once lived in Ferguson, also poured out several bottles of water and filled them with milk, to help wash tear gas out of people's eyes.
Things must change
Community leaders in Ferguson have grown tired of the violence smudging peaceful protests and insisted earlier Tuesday that things must change.
Authorities requested there be one night of peace, and some residents seemed to grant the request.
Some who were on the streets during the day cleared out by nightfall, saying they, too, were tired of what went on after dark, including the militaristic police response.
Others from the community donned T-shirts printed with the word "peacekeeper," and got in between budding tensions to defuse them. Some talked emphatically with young men, who appeared to want to charge at the police.
Demand for cameras
Ferguson leaders have vowed to recruit more African-Americans to join the overwhelmingly white police force in the largely African-American neighborhood.
And they signaled their intention to raise money so that all officers and police cars would be outfitted with vest and dash cams.
Such cameras could have helped clear up many questions surrounding Brown's death: Was he executed by a police officer while holding his hands in the air, or was he shot after rushing at Officer Darren Wilson?
Police and protesters have blamed agitators -- including many from outside Ferguson -- for the violence marring the protests. According to the jail records, some of those arrested Monday night came from New York, California, Texas and Alabama.
Many have also criticized the police response.
Gen. Russel Honore, who handled crowd control in the chaos that ensued after Hurricane Katrina in New Orleans in 2005, joined them late Tuesday.
"You're there to protect people," he said. "They need to sense that from you." Looking at crowd members through the scope of a gun sends the wrong message, he said.
Demands for prosecution
After days of cries for justice, the wheels will grind forward on Wednesday.
U.S. Attorney General Eric Holder plans to visit. On a state level, a prosecutor is expected to start presenting evidence to a grand jury, which will consider whether or not to indict Officer Wilson.
But charges against the officer from either investigation will not come quickly, CNN law enforcement expert Tom Fuentes said.
In the state investigation, forensic details, the autopsy results and toxicology tests are still pending.
And federal investigators will plod ahead slowly, Fuentes said. "If they choose to bring charges against Officer Wilson, they have to go to trial in 90 days."
So, they will take their time to make their case thoroughly, he said. "They will rather be slow than wrong.
TM & © 2014 Cable News Network, Inc., a Time Warner Company. All rights reserved.