CHICAGO — The off-duty Chicago Police officer who fatally shot Jose Nieves following a verbal altercation has been relieved of his powers, police said Tuesday.

The 57-year-old officer, who was assigned to the Mass Transit unit, shot Nieves in the 2500 block of North Lowell Avenue in Hermosa about 9:15 a.m. Monday, according to authorities.

Police said the officer's weapon was the only gun found on the scene. Nieves, 38, was shot multiple times.

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Police Supt. Eddie Johnson earlier this week said the two knew each other from "a confrontation" that occurred "a few weeks ago." The officer was in Hermosa visiting someone Monday, police said, and had clashed with Nieves on multiple occasions.

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

In a news release Tuesday, Chicago Police spokesman Anthony Guglielmi​ said "Johnson has relieved the officer involved in the incident of his police powers. The Chicago Police Department continues our fact-based investigation of the incident, in parallel with the Independent Police Review Authority."

According to NBC, Nieves worked construction and bar security, and lived on the Northwest Side.

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.”

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

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