The Bureau of Criminal Apprehension has joined the Otter Tail County Sheriff's Office in investigating the death, which occurred Saturday near Underwood.
Sheriff's deputies and first responders arrived at the home on the 31000 block of Hwy. 1 about 5:05 a.m. and found a baby unconscious and not breathing. A family member was giving the baby CPR, said Lt. Keith Van Dyke of the Sheriff's Office.
Despite efforts by medical personnel and law enforcement, the baby died at the scene.
"At this time it is believed the death is accidental," Van Dyke said.
An autopsy was being conducted Sunday by the Midwest Medical Examiner's Office.