(SAN DIEGO) -- A chilling discovery -- and recently-released emergency dispatch audio -- offer new twists into a double-murder mystery that has baffled San Diego police.
Gianni Belvedere, 24, his fiancée Ilona Flint, 22, and his little brother Salvatore, 22, visited a San Diego shopping mall on Dec. 23. Early Christmas Eve morning, Ilona and Salvatore were found shot in their car outside the mall. Both would die from their wounds.
Before she died, Flint managed to call 911. Newly-released emergency dispatch audio identifies a potential suspect at the scene, someone who "possibly left in a 2008/2011 dark gray Honda Civic four-door."
Gianni Belvedere -- who has not been named a suspect in the case -- hasn’t been seen since.
This past weekend, nearly a month after the shootings, Belvedere's green Camry was found about 100 miles away with a man's body inside the trunk. Police have yet to identify the body.
The smell caused a passer-by to call police. "I usually park in that same spot," witness Gabby Alcarez said. "The odor is pretty strong, like when I passed by it."
The Press-Enterprise captured video of officials towing away the car. An autopsy will be performed this week to identify the body found in Belvedere's car.
Investigators say they still have no suspects and no motive in the case, but they don't believe it was a robbery.
"As of this juncture, we still do not know a motive of why this occurred," San Diego Police Lt. Mike Hastings said Dec. 26.
The family of Belvedere's fiancé released a statement to ABC News overnight, expressing concern for the missing 24-year-old.
"We consider Gianni Belvedere to be our son as much as the Belvederes consider Ilona to be their daughter," the statement reads. "The Belvedere and Flint-Jones families thank the media for respecting our privacy during this difficult time."
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