People in the Board of Trade Building in Wheeling rushed to the windows, horrified at what they were seeing.
Dr. Tricia Bailey, clinical psychologist, acted quickly to ensure the safety of her clients and staff.
Dr. Bailey says she had two brand new clients in the office, one winding up a session, the other in the waiting room.
When she heard the barrage of shots, she looked out and saw flashing lights and officers with weapons everywhere.
She took both clients and her secretary to her inner office to shelter in place.
"We locked the outer door which was really a fire door so we bolted that and locked my office door and my inner office door," she said.
They were safe, but she said the clients were distraught and fearful, one was sobbing.
Dr. Bailey says it's sadly ironic that they had to endure a trauma in a psychologist's office.
"They're coming to a therapist's office to feel better about themselves and their life, not to be traumatized," she said. "So it was pretty overwhelming and we had to do some de-briefing with both people."
Upstairs on the Board of Trade Building's fourth and fifth floors, employees could reportedly watch every move the shooter made.
"They were able to give valuable details and information about what they were seeing from their vantage point, to the officers," he said.
Dr. Bailey says she didn't know the shooter, but her first thought was that it was a suicide-by-cop.
"This individual had a background in law enforcement so he would have had the knowledge that if he behaved in this manner, he certainly would have been well aware of the outcome," she noted.
She says even his choice of the federal building as the site points to that.
"You have massive amounts of officers coming in all directions, and maybe that was the intent, to go out in a blaze of glory, I don't know," she said.