Anna Hernandez was found dead in an open area off the 2900 block of Market Street shortly before 5:30 p.m. Wednesday, according to San Diego police.
The cause of death was not immediately apparent, but an autopsy determined that she died of gunshot wounds to her upper body, Lt. Mike Hastings said.
The junior at High Tech High School had gone missing five days before her body was found. A friend of hers, 12-year-old Nelly Espinoza, reportedly disappeared the same day, and her whereabouts remain unknown. It was unclear if the two left their respective homes together.
Authorities have not announced any arrests in the case or released suspect information.
“Homicide detectives continue to work to develop suspect information in this case,'' the lieutenant said late Monday afternoon.
Hundreds of friends have left flowers and candles at the spot where her body was found.