Medical examiners say "blunt force head trauma" is what killed the 4-month-old son of a Marine stationed at MCAS Miramar.
Investigators charged a local Marine after the death of his 4-month-old son.
Michael Bixby was arrested in connection with the case at 12:15 p.m. on Tuesday by San Diego Police homicide detectives. Police said he is accused of the murder of his infant son.
Medical examiners said that "blunt force head trauma" killed the child of the Marine, who is stationed at Marine Corps Airs Station Miramar.
Andru Bixby died Thursday morning at Children's Hospital, about 14 hours after his 22-year-old father called 911 to report that Andru had stopped breathing. Andru's mother had been watching him and his 18-month-old brother before leaving for school when Michael came home.
Michael was questioned after he first reported the child's injuries, but he was initially released pending the outcome of the investigation.