The shooter, described by police as a short male with a mask, remains at large and is evading police on foot.
The university's interim deputy chief confirmed that "some" of the gunshot victims have life-threatening injuries.
The campus has been secured, and officials have issued a shelter-in-place order to the greater community.
Video shared of the scene has captured multiple police cruisers racing to the campus as well as documenting officials' efforts to secure the campus.
Local media reported that Michigan State Police troopers had been seen on campus with rifles, instructing individuals on campus to remain indoors and stay away from windows. At 5,200 acres, the campus is considered one of the largest US universities by area.
The FBI's Detroit office and the Bureau of Alcohol, Tobacco Firearms and Explosives are responding to the scene.
The shooting occurred on the eve of the fifth anniversary of the Parkland High School shooting that killed 17 people.