Story highlights Ferguson-Florissant district pushes back the start of school

"We understand the anger ... that people want answers," police chief says

Officials decline to identify officer who shot the teen, citing safety concerns

Family's attorney: Police should be transparent, "not try to sweep it under the rug"

A new witness in the police shooting of unarmed teen Michael Brown in Ferguson, Missouri, told CNN that Brown and the police officer tussled at the police car window, then the officer shot the teen multiple times, as Brown backed away.

"What I saw was when Michael and the cop were wrestling through the window," Tiffany Mitchell told CNN's Don Lemon. A shot was fired while Brown was out the window. He got free, and the officer got out of the vehicle, followed Brown and shot him, she said.

He raised his hands, and the officer kept firing, she said.

Police fired tear gas at a crowd of protesters late Wednesday for another night, as the group gathered to protest Brown's deadly shooting.

Officers in riot gear then marched toward the protesters near a burned out gas station, which has become the gathering point for demonstrations.

Police announced that they no longer considered the protest peaceful, before they fired the canisters, CNN producer Yon Pomrenze said. People fled in all directions, as the stinging clouds wafted by them.

A separate small group of over a dozen people gathered outside Ferguson's police station holding up signs and chanting protests for a fifth day.

Officer not named

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Police have said Brown died in a dangerous struggle after trying to grab the officer's weapon, but witnesses say it seemed a brazen act of aggression by the officer on Saturday, and that Brown was unarmed and not threatening.

On Wednesday, Ferguson Police Chief Thomas Jackson told CNN that the officer had been hit and suffered swelling on the side of his face. He was taken to a hospital and released the same day, Jackson said.

Five days have passed since Brown's killing, and the public still does not know the name of the person who pulled the trigger.

There have been cries of a cover-up.

"That doesn't give the community confidence. That doesn't make it transparent," attorney Benjamin Crump told reporters. "And remember, we've got a long way to go before this community starts to believe that the police are going to give them all the answers and not try to sweep it under the rug."

Crump was one of the attorneys who represented the family of Trayvon Martin, the teenager who was killed in a 2012 altercation with Florida man George Zimmerman.

But Mayor James W. Knowles said police have received death threats against the officer and his family. They want to prevent further violence, he said.

Hackers have gone after his personal information and worked people up against members of government and the police, he said.

Trouble at night

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Police have asked protesters to restrict their gatherings to daylight hours, after violence has broken out repeatedly after nightfall. Protests during the day have been peaceful.

Protests on Sunday and Monday ended with clashes with police and looting . Police have made 47 arrests after Brown's shooting, KMOV reported.

"We understand the anger; we understand that people want answers. We understand that we've got a problem, but we're just asking people to be peaceful," Jackson said.

The Ferguson-Florissant School District announced that it was pushing back the start of classes this year. School had been scheduled to resume Thursday.

Civil rights

Federal civil rights investigators and the FBI carry out their own inquiry into the controversial case. In the town of 21,000, there's a history of distrust between the predominantly black community and the largely white police force.

"Race relations is a top priority right now and, as I said, I'm working with the Department of Justice to improve that," Jackson told reporters Wednesday.

Only three of the city's 53 officers are African-American, and Jackson said he is working to change that.

Dorian Johnson, who said he saw the shooting, told CNN on Tuesday that the officer who opened fire is white.