The stabbing happened around 8:30 a.m. in the 6400 block of West Irving Park Road, Chicago police said.
A 24-year-old man was inside a building when he "tried to de-escalate an altercation," and he was stabbed multiple times, police said.
The victim was taken to a hospital in critical condition. A suspect was taken into custody, CPD said.
Sources told ABC7 the Burger King employee who was stabbed has since been released from the hospital.
"We are saddened to learn of the incident that occurred at the Burger King restaurant located at 6400 W. Irving Park," a statement from a Burger King spokesperson read. "The Franchisee of this location is cooperating with local law enforcement in their ongoing investigation, and is actively providing support to all those impacted."
No further information was available as Chicago police continue to investigate.
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