A man upset about a job demotion gravely wounded the chief executive officer of his company in a downtown Chicago office building and then fatally shot himself, police said on Thursday.

The 54-year-old CEO was taken to the hospital with gunshot wounds to his stomach and head, police said. They said the dead gunman was 59 years old.

Chicago Police Superintendent Garry McCarthy could not confirm the name of the company but said it was on the 17th floor at 231 S. LaSalle St., the address of the software company ArrowStream.

McCarthy described the shooting as an isolated workplace incident.

“He’s a longtime employee who comes in with a backpack like an employee normally does,” he said of the gunman. “It’s basically a personal thing. The company is downsizing and a number of people were demoted…

“He asked for a one-on-one with the CEO and that’s when this happened,” McCarthy said.

Steven LaVoie is CEO, chairman and founder of ArrowStream and is married with three daughters, according to the company’s website.

Police would not give the identities of either the alleged shooter or the victim, but a spokeswoman for Northwestern Memorial Hospital confirmed that LaVoie was hospitalized in critical condition.

Police were interviewing 10 witnesses who were on the 17th floor of the Bank of America building where the shooting happened before 10 a.m., he said.

Neil Machchhar, an information technology specialist who works on the 14th floor of the building, told Reuters an announcement came over the building’s public address system telling employees to “stay in place” because there was an armed intruder in the building.

“The person on the P.A. sounded a little shaky,” he said.

No one from ArrowStream was available for comment.