Darren Wilson, the Ferguson, Mo., police officer whose fatal shooting of Michael Brown touched off more than a week of demonstrations, suffered severe facial injuries including a bone fracture near one eye and was nearly beaten unconscious by Brown moments before firing his gun, a source close to the department's top brass told FoxNews.com.

“The Assistant (Police) Chief took him to the hospital, his face all swollen on one side,” said the insider. “He was beaten very severely.”

According to the well-placed source, Wilson was coming off another case in the neighborhood on Aug. 9 when he ordered Michael Brown and his friend Dorain Johnson to stop walking in the middle of the road because they were obstructing traffic. However, the confrontation quickly escalated into physical violence, the source said.

“They ignored him and the officer started to get out of the car to tell them to move," the source said. "They shoved him right back in, that’s when Michael Brown leans in and starts beating Officer Wilson in the head and the face."

The precise extent of Wilson's injuries are unclear. The source told FoxNews.com on Wednesday that the officer had sustained a fractured eye socket in the incident, and repeated that assertion early Friday morning, in response to a conflicting report on the severity of the injuries.

The source claims that there is "solid proof" that there was a struggle between Brown and Wilson for the policeman’s firearm, resulting in the gun going off – although it still remains unclear at this stage who pulled the trigger. Brown started to walk away according to the account, prompting Wilson to draw his gun and order him to freeze. Brown, the source said, raised his hands in the air, and turned around saying, "What, you're going to shoot me?"

At that point, the source told FoxNews.com, the 6-foot-4, 292-pound Brown charged Wilson, prompting the officer to fire at least six shots at him, including the fatal bullet that penetrated the top of Brown's skull, according to an independent autopsy conducted at the request of Brown's family.

Wilson was left dazed by the initial confrontation, the source said. He is now "traumatized, scared for his life and his family, injured and terrified" that a grand jury, which began hearing evidence on Wednesday, will "make some kind of example out of him," the source said.

The source also said the dashboard and body cameras, which might have recorded crucial evidence, had been ordered by Ferguson Police Chief Thomas Jackson, but had only recently arrived and had not yet been deployed.

A spokesman for the St. Louis County Police Department, citing the ongoing investigation, declined late Wednesday to say whether Wilson required medical treatment following the altercation.

Edward Magee, spokesman for St. Louis County Prosecutor Robert McCullough, said the office will not disclose the nature of the evidence it will reveal to a grand jury.

"We'll present every piece of evidence we have, witness statements, et cetera, to the grand jury, and we do not release any evidence or talk about evidence on the case."

Nabil Khattar, CEO of 7Star Industries – which specializes in firearms training for law enforcement and special operations personnel – confirmed that police are typically instructed to use deadly force if in imminent danger of being killed or suffering great bodily injury.

“You may engage a threat with enough force that is reasonably necessary to defend against that danger,” he said.

Wilson is a six-year veteran of the Ferguson police force department, and has no prior disciplinary infringements.

Massive protests have since taken over the St. Louis community, prompting Missouri Gov. Jay Nixon last Thursday to place Highway Patrol Capt. Ron Johnson at the helm of security operations in an effort to calm ongoing tensions. The federal government is also investigating the death, and Attorney General Eric Holder has taken the lead – calling “the selective release of sensitive information” in the case “troubling.”

On Friday, Ferguson police released surveillance video showing Brown stealing cigars from a convenience store just before his death. Jackson came under intense criticism for disclosing the tape and a related police report as he also insisted that the alleged robbery and the encounter with Wilson were unrelated matters. Brown’s family, through their attorney, suggested the tape’s release was a strategic form of “character assassination.”

However, FoxNews.com’s source insisted that there was absolutely no spin agenda behind the tape’s release and that there were a number of Freedom of Information Act (FOIA) media requests filed by media outlets seeking it. Tom Jackson is said to have waited on publicly releasing it, and did not want it shown until Brown’s grieving mother first had the chance to see it.

“He defied the FOIAs as long as he could,” noted the insider. “A powerful, ugly spin has completely ruined public discourse on this whole situation.”

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