A 16-year-old Simi Valley girl was arrested at her high school and charged with the murder of a newborn baby whose body was found in a dumpster in January, police said. The girl was booked at the Simi Valley police station and later transferred to Ventura County Juvenile Hall in Ventura, Lt. Don Austin said. He declined to identify the girl or her high school. Austin said investigators got a break when officers conducting an unrelated burglary investigation stumbled across information that led to the girl. He declined to elaborate. Austin said the break ended a frustrating investigation that "didn't go anywhere" for months. An autopsy determined that the baby died of exposure shortly after her birth.