A Wisconsin firefighter who was shot and killed while responding to a medical call Wednesday was the married father of three young children, authorities said.
Firefighter Mitch Lundgaard was a 14-year veteran of the Appleton Fire Department, Appleton Fire Chief Jeremy Hansen said at a press conference Thursday.
Lundgaard died in a local hospital hours after being shot at the Transit Center in Appleton, about 100 miles north of Milwaukee.
Appleton Police Chief Todd Thomas said that Appleton fire and police personnel responded to the bus terminal Wednesday at about 5:30 p.m. to assist a 47-year-old male who was arriving on a bus from out of the area. Initial reports indicated that the man was having a seizure, Thomas said.
After receiving assistance from first responders on the bus, the man left the bus was walking toward the nearby library building when he displayed a handgun and shots were exchanged between him and police, Thomas said. Lundgaard was struck, as was an Appleton police officer and a female bystander.
Police shot the man, who was transported to a local hospital where he died.
The police officer was treated and released from the hospital on Thursday, while the woman was still being hospitalized in stable condition.
The Green Bay Police Department is leading the investigation into the incident.
"It was a very quick scene," Meghan Cash of the Appleton Police Department told ABC Green Bay affiliate WBAY. "We had to get people to the hospital quickly."
Tori Mourning, a witness, told WBAY that at first it sounded like a lawnmower backfiring and then "I heard it again -- I looked up because we can see the bus stop from my bedroom window."
"I saw the guy shoot a female, and she went down," Mourning added, "and another shot was fired, and there was another male, and he went down, and then I saw the shooter flee."
Firefighters lined the street overnight as emergency vehicles escorted Lundgaard's body to the Milwaukee County Medical Examiner's Office.
ABC News' Olivia Rubin and Ahmad Hemingway contributed to this report.