Paul A. Knobbe wrapped up his shift Tuesday evening as a handyman at the Winner gas station in south Minneapolis and was ready to head home.

It was a three-block walk for Knobbe, from the station at the corner of 34th Street and Cedar Avenue S., to the duplex he shared with a friend. He made the trek almost every night.

But it was in that alley, behind the chain link fence that wraps around the rear of the station, police said, that Knobbe was gunned down by an as-yet-unidentified assailant about 10:10 p.m. Tuesday. According to scanner traffic, several bullets of an unspecified caliber tore into his back.

Police haven't identified a motive for the slaying, although co-workers and neighbors speculated that it may have been a robbery gone wrong.

Officers responding to the shooting performed lifesaving measures on Knobbe, who was identified by co-workers and in police records, before paramedics arrived. He was later taken to Hennepin County Medical Center, where he was pronounced dead on Wednesday morning, a police spokesman said.

His death came as the city passed a grim milestone — more than 300 people have been shot so far this year, about 15 percent more than were shot in all of 2015.

Knobbe was at the station moments after it closed when he was shot, said owner Fazal Mahmoud.

Mahmoud, who said Knobbe's job was to keep the parking lot clean, recalled while tending to customers Wednesday that his employee was "a good guy with a good heart. I'm still shaking. This is bad news."

Another employee, who declined to give his name, said Knobbe was a hard worker and did whatever was asked of him — sweeping leaves from the front of the station and mopping the floor, among other jobs. When he was working, the store clerk said, Knobbe would perch on the bar stools near the store's entrance, sipping coffee and watching the flow of customers going in and out.

Samuel Mulari, who runs an auto shop across the street, recalled Knobbe as a quiet, kind and helpful man.

"He was a handyman, cleaning the leaves and cutting the grass," for whoever would pay him, Mulari said.

"That was an innocent guy from what I know," he said. "Sometimes, you don't know people, but from what I saw, he was a good person."

Since the shooting, homicide investigators have fanned across the block, interviewing witnesses and reviewing surveillance footage from cameras at nearby businesses, in hopes of generating leads in the case.

A pair of detectives walked over to the auto shop Wednesday and asked for any surveillance video, he said.

It was the city's fourth homicide in less than a week, and there have been no arrests made in any of the cases. Minneapolis' homicide tally this year stands at 35.

The spate of deadly gunfire in the city began last Thursday morning, when 50-year-old Michael M. Whitelaw was shot in his apartment in the 1600 block of Glenwood Avenue N.

Late Friday, Dana L. Logan, 46, was shot in the chest while sitting in her car near 36th and Queen avenues N.

About 5 a.m. Saturday, Richard D. Ambers, 31, was in a car on Bryant Avenue N. near 48th Avenue, when several shots hit him.

Anybody with information about any of the recent killings can text the Police Department at 847411. Texters should enter MPD, a space and then their information. They also can call the department's tip line at 612-692-8477.

Staff writer Tim Harlow contributed to this report.

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