ABC News(CHICAGO) — Chicago police shot and killed a man Saturday night igniting protests in the city, clashes with cops and resulting in the officer being placed on desk duty just hours after the shooting. The protests led to multiple officers being injured, police said.

Chicago Police Chief Fred Waller said a group of officers patrolling the city’s South Shore neighborhood at about 5:30 p.m. saw a person they believed to be armed and confronted him.

A struggle followed and the man was fatally shot. None of the officers were injured.

“Some officers working a foot post, walking along 71st Street, saw a subject they thought might have been armed from the bulge around his waistband,” Waller said at a press conference Saturday night. “After that, they approached the subject, who became combative and as he became combative, flailing away, he broke free from the officers and they thought he appeared to be reaching for a weapon — which he did have a weapon on him — and officers tragically shot this man.”

Waller called the shooting a “tragic incident.” Police said only one officer opened fire, striking the man.

The man was pronounced dead at Jackson Park Hospital, according to officials. He has not been identified.

The police recovered a semiautomatic-type weapon and magazines from the suspect.

The suspect did not fire his weapon, Waller said.

In the immediate aftermath of the fatal shooting, protests began in the area. Chicago ABC station WLS captured video of protesters pushing and shoving back and forth with police officers.

Waller said three or four officers suffered minor injuries in the protests when demonstrators threw rocks and glass bottles at them. Waller said a few protesters were arrested, but did not have a specific number. Anthony Guglielmi, chief communications officer for the Chicago Police Department, later tweeted four protesters were arrested.

The Civilian Office of Police Accountability said in a statement to WLS that there would be a “thorough, objective and unbiased investigation and requests the public’s patience and cooperation.”

Just hours after the shooting, the Chicago Police Department released a preliminary statement about the shooting saying the officer who fired the shots would be “placed on routine administrative duties for a period of 30 days.”

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