Darren Wilson resigns from Ferguson Police Department

The white police officer who killed Michael Brown has resigned from the Ferguson Police Department, his attorney said Saturday, nearly four months after he shot dead an unarmed black 18-year-old, fueling protests that have rocked the St. Louis suburb and the nation.

Darren Wilson, 28, has been on administrative leave since the shooting on Aug. 9. His resignation was announced Saturday by one of his attorneys, Neil Bruntrager. The resignation is effective immediately, Bruntrager said. The St. Louis Post-Dispatch reported that Wilson cited security concerns as a reason behind his resignation.

"In terms of his safety, it is probably the best thing for him," said Cynthia Burnes, 26, a nurse's assistant from St. Louis who was among about 50 people gathered in front of the Ferguson police headquarters on Saturday evening.

"He is black-listed from this moment on," she told Reuters.

A man was arrested at the scene after he knelt in the middle of the street with his hands raised, chanting "Hands up, don't shoot," a common refrain at Ferguson protests.

A grand jury spent more than three months reviewing evidence in the case before declining to issue any charges against Wilson in November. He told jurors that he feared for his life when Brown hit him and reached for his gun.

The U.S. Justice Department is still conducting a civil rights investigation into the shooting and a separate probe of police department practices.

After the shooting, Wilson spent months in hiding and made no public statements. He broke his silence after the grand jury decision, telling ABC News that he could not have done anything differently in the encounter with Brown.

Wilson said he has a clean conscience because "I know I did my job right." Brown's shooting was the first time he fired his gun on the job, he said.

Asked whether the encounter would have unfolded the same way if Brown had been white, Wilson said yes.

Wilson began his career in nearby Jennings before moving to the Ferguson job a few years ago. He had no previous complaints against him and a good career record, according to Police Chief Thomas Jackson, who called Wilson "an excellent police officer."

Wilson will not receive pension benefits, according to his attorney. However, his supporters have managed to raise about $500,000, mostly to cover legal fees. It is unclear how much of that money Wilson will have access to.

Speaking to reporters Sunday, Ferguson Mayor James Knowles said that he would aim to ensure the local police force is "more reflective of the demographics of Ferguson" in the future. To that end, he said he would form a civilian review board to monitor the police, strengthen incentives for police officers to live within the community and begin a scholarship program for attracting more black recruits onto the force.

As reported by the St. Louis Post-Dispatch, Wilson's resignation letter reads:

"I, Darren Wilson, hereby resign my commission as a police officer with the City of Ferguson effective immediately. I have been told that my continued employment may put the residents and police officers of the City of Ferguson at risk, which is a circumstance that I cannot allow. For obvious reasons, I wanted to wait until the grand jury made their decision before I officially made my decision to resign. It was my hope to continue in police work, but the safety of other police officers and the community are of paramount importance to me. It is my hope that my resignation will allow the community to heal. I would like to thank all of my supporters and fellow officers throughout this process."

Also on Saturday, activists shifted gears by setting off on a seven-day march from Ferguson to Jefferson City, the state capital. The march, reminiscent of the civil rights marches of the 1960s, was organized by the National Association for the Advancement of Colored People (NAACP).

All told, about 100 marchers were expected to make the entire journey, with about 1,000 expected to be part of the final leg of the march, said NAACP staff member Jamiah Adams.

As tensions rose in Ferguson over the past week, members of the Oath Keepers — a group that says it exists to defend constitutional rights — have appeared around town, saying they're there to safeguard the rights of protesters. Many of them were perched on rooftops, clad in military fatigues and armed. The police ordered them to leave those rooftops on Saturday.

Al Jazeera and wire services