A body found in the trunk of a car on Saturday was confirmed to be Gianni Belvedere, a man missing in a Christmas Eve murder investigation.

His family confirmed but police have not yet confirmed if it was really him.

Gianni Belvedere, together with his fiancée Ilona Flint and his brother Salvatore went on a shopping at San Diego, Dec 23. The day after, Dec. 24, Salvatore and Iona were found dead in the car without Gianni.

Nearly month after the incident, the Riverside Police Department was tasked to check on a car 100 miles away. Belvedere's car was found with a man's body on its trunk.

The officer who checked the car said that the car's plate number is related with that of Belvedere's case. The police have not been identified how long the car was parked there.

At NBC 7, a family member confirmed that the man on the trunk was actually the missing Gianni.

According to the police, they still have no suspect regarding the double homicide case. With such condition, the police are keeping everything closed and out of the media as the investigation run on.

Former FBI agent Brad Garret said in a morning show on Monday, "With these types of shootings, it really goes back to some sort of revenge: you owe me money, you owe me drugs, etc."

"Cell phones, emails, there's something in their background that led to this ... and I'm going to guess that it is out there," Garrett added.

Mike Vasquez, Riverside County Sheriff told 10 News on Saturday that the body needs to be identified and an autopsy will be done by Wednesday this week.

Mike Hasting of San Diego Police Department mentioned that $10,000 reward for finding Gianni will soon be rewarded for the arrest of the suspect in the case.