HERMOSA — A man was fatally by an off-duty officer in Hermosa Monday morning after what police described as "a verbal altercation" and a confrontation weeks ago.

The off-duty officer, who was assigned to the Mass Transit Unit, shot the man in the 2500 block of North Lowell Avenue in Hermosa at 9:14 a.m., according to police.

Jose Nieves, 38, was taken to Advocate Illinois Masonic Medical Center where he died, according to the Cook County Medical Examiner's office. A Tuesday autopsy showed Nieves had been shot multiple times, and his death was ruled a homicide.

Police said the officer's weapon was the only gun found on the scene.

Chicago Police Supt. Eddie Johnson said at a press briefing that the two knew each other from "a confrontation" that occurred "a few weeks ago."

The officer, age 57, was in the neighborhood visiting someone, police said, and the two reportedly had had a number of previous clashes.

Nieves worked construction and security at a bar and lived in the Northwest Side neighborhood, NBC reports.

"I have a lot more questions than I do answers at this time," Johnson said.

According to a Police Department statement: "The incident escalated, resulting in the off-duty officer discharging his weapon, striking the male multiple times."

A woman who was identified as a sister of Nieves told CBS2: “If you are an officer, and you are getting shot at, and your life is in danger, I understand. But if a person doesn’t have a weapon, it doesn’t give you the right to take out your weapon and shoot at that person. It does not.”

Monday's shooting followed another one early Sunday in West Pullman.

At 2:20 a.m., police responding to reports of gunshots in the 12000 block of South State Street saw a car speed through a stop sign, according to a police statement.

Police tried to stop the car, but it sped for several blocks on State Street before hitting hit several cars and crashing into the pursuing police car.

Police got out of their car and approached the crashed car.

"As officers approached the offender, they issued several verbal commands ordering the subject to exit his car," according to a police statement. "The offender ignored officers and began to make furtive movements in the driver’s compartment."

The man resisted being taken out of the car, police said. An officer, who said he believed the man was armed, shot him several times. The man and two officers were taken to the hospital with injuries.

Police and the Independent Police Review Authority are investigating the incident.

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