Kalamazoo County Undersheriff Paul Matyas told local Fox affiliate 17 News that six people had been shot and killed at a Cracker Barrel restaurant and a car dealership.
Matyas said that the suspect, who remains on the loose, is a white male in his late 50s driving a blue Chevy HHR station wagon who appears to be randomly shooting people.
The shootings "all appear to be related" to the same gunman, Matyas told 24 Hours News 8.
"I would say definitely it's a serial killer," he said.