MINNEAPOLIS (AP) -- Authorities say a 19-year-old man has been arrested on suspicion of murder in the death of his 2-month-old son in a Brooklyn Park apartment building.

Officers were called to the building Tuesday on a report of a baby not breathing. Police administered first aid, but the child died about an hour later at a Robbinsdale hospital.

On Friday, the Hennepin County medical examiner says the child died of "multiple blunt-force injuries" inflicted during a homicide.

The boy's only caregiver at the time was his father, who is being held in the Hennepin County jail pending formal charges.