Mitchell F. Lundgaard, a 14-year veteran of the department, was hit by gunfire when the medical emergency escalated between the man suffering from a seizure and police, WBAY reported.
After rendering aid to the 47-year-old man, the patient left the bus and began walking to a nearby library, KCCI reported. The man then flashed a handgun and started firing on police, which is when Lundgaard was shot, investigators said.
A police officer and bystander were also injured in the gunfire, authorities said. The suspect in the shooting was taken to a hospital, where he was pronounced dead.