Ypsilanti Police officers on the scene reported explosions coming from inside, likely caused by oxygen tanks, as they helped four residents evacuate, Madison said. A fifth resident jumped from a second-floor window, but was not injured.
Two people were taken to the University of Michigan Medical Center and a third was taken to St. Joseph Mercy Hospital with what are believed to be non life-threatening injuries. The residents ranged in age from 18 to 63, officials said.
A firefighter was treated at the scene for an injured leg, Madison said.
The fire started in a first-floor bedroom and spread to the second floor and attic. The cause remains under investigation.
The structure, believed to be a boarding house, was a total loss. The Washtenaw County Chapter of the American Red Cross is assisting two residents with shelter.
Firefighters from Ypsilanti and Pittsfield townships, and the city of Ann Arbor assisted at the scene.