Miguel Chavez, 6, died in a fire Tuesday morning, which left his brother Julio, 4, in critical condition. His mother, Silvia Chavez, had left them unattended to go to work, the Detroit News reported.
Neighbors said the family was using a space heater because the home's heat was turned off.
The boys were transported to a hospital by a Rescue Squad vehicle, the newspaper said, because a better-equipped EMS (emergency medical services) vehicle was not available.
Detroit Fire Department officials said CPR was performed on both children on the way to the hospital. Both suffered smoke inhalation, Capt. Frank Maiorana said.
A Rescue Squad vehicle is not typically used as a substitute for an EMS vehicle, fire officials said, the newspaper reported.
"They don't do that normally, but EMS wasn't on the scene, and where minutes count, they (the Rescue Squad) have oxygen and everything handy," said Senior Fire Chief Lewis Roelans.
The newspaper said two ambulances were stationed closer to the scene, but one was responding to another emergency, the other not operable.
"This continues to be a major problem," said Dan McNamara, the city's fire union president. "With the (fire) company closings, we're now seeing increased response times, and a higher number of casualties and injuries. Nobody in the administration seems to be paying attention."
Councilman Kwame Kenyatta added, "A lot of work has to be done. It's all about management."