The stabbing happened around 5 p.m. near West Randolph Street and North Racine Avenue, Chicago police said.
It all played out before a beautiful weeknight of live music and charity gatherings on the patio could get rolling in the West Loop.
The victim, a 47-year-old man, died after being taken to a hospital in critical condition, Chicago police said.
The offender, a 41-year-old man, is in custody, police said.
The two men involved were coworkers at the City Winery, and a dispute between them inside the business led to the deadly stabbing, a spokesperson for the Chicago fire Department told ABC7. One man stabbed the other repeatedly in the back and chest.
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As a concert venue turned to a crime scene Wednesday, a local artist offered a small consolation hugs and autographs to disappointed fans.
West Side native R&B artist Danny Boy Steward was in the building prepping for his planned performance that was set to begin just a few hours later.
"I didn't know anything because we were in the back doing a sound check and the front part of the building was blocked off," he said. "They said that it was something that had occurred. We really didn't know what was going on 'til they cut the show."
Chicago police had blocked off lanes of an already-congested Randolph Street.
"Kind of shaken up. Sad for all the work that happened and was involved, but also just sad that this happens," said Cathleen Himes, who was supposed to attend the event at City Winery.
Concertgoers and charity dinner attendees had already showed up ready for a night of frivolity, only to be met with crime scene tape and detectives deep in a fresh investigation.
"It's really sad that people go through something like that," ChiLites concertgoer Mack Miller said. "I don't know what it was about, who got stabbed... I don't know any of that, but all I know is it's useless. It's really sad."
Just this past Saturday afternoon, a few blocks to the east, EMTs raced to a store at Randolph and Wabash when someone stabbed a security guard.
Last Friday, Eataly in River North was temporarily closed after a gun discharged during a fight between employees there.
No further information about the stabbing was immediately available.
Police continue to investigate.
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