A man is in critical condition after he was stabbed inside a Burger King on Chicago's Northwest Side on Friday morning. 

Chicago police said around 8:30 a.m., a 24-year-old man was inside the restaurant in the 6400 block of West Irving Park Road when he tried to de-escalate a fight. It is not clear what led up to the incident. 

Police said the man was then stabbed multiple times.

He was taken to Lutheran General Hospital in critical condition, police said.

One person was taken into custody, police said. 

Area Five detectives are investigating.

Burger King released a statement, writing, "We are saddened to learn of the incident that occurred at the Burger King restaurant located at 6400 W. Irving Park. The Franchisee of this location is cooperating with local law enforcement in their ongoing investigation, and is actively providing support to all those impacted."