The Mcstay Family / via Zuma Press The skeletal remains of four people were found this week in the desert outside of Victorville, Calif. Joseph McStay, 40, his wife, Summer, 43, and their two kids Gianni, 4 and Joseph, 3, vanished in 2010 from their home. The remains of two of four bodies have been identified as the missing husband and wife but it remains unclear if the other bodies are the two young sons.

More than three years ago the McStay family -- Joseph, Summer and their two young sons – seemed to vanish into thin air, but Friday authorities confirmed that four sets of skeletal remains found in California’s Mojave Desert are likely those of the couple and their two boys.

San Bernardino County Sheriff John McMahon said at a press conference that the remains were identified through dental records as those of Joseph McStay, 40, and his wife, Summer, 43.

Authorities are in the process of identifying additional skeletal remains that are believed to be those of the couple's sons, Gianni and Joseph Jr., who were 4 and 3, respectively, at the time of their disappearance.

The case is now being investigated as a multiple murder. McMahon said no suspect or suspects have been identified but held out hope that evidence at the scene where the bodies were found would eventually lead investigators to whoever was responsible for the killings.

"We will put the pieces together with all hope of solving this crime, McMahon said. "There is ... evidence at the scene that will help the investigation. The investigation will lead us in the direction of the suspects as we get more information."

The family was last heard from on Feb. 4, 2010. Detectives found no signs of a struggle at the family's Fallbrook, Calif., home and their empty white Isuzu Trooper later was found in San Ysidro mall parking lot, a short distance from the U.S.-Mexico border.

The San Diego County Sheriff's Department, working with the FBI, fielded hundreds of tips and, as part of its investigation, reviewed border crossing records and security videos on the suspicion that the family might have crossed into Mexico of their own free will. But no clear evidence emerged pointing investigators to the family's whereabouts or their fate.

The break in the case came Monday when a motorcyclist off-roading through a remote desert area reported finding bones and called authorities.

Additional coverage from NBCSanDiego.com

San Bernardino County Sheriff's homicide investigators and coroner's officials examined the bones and discovered two shallow graves, where additional skeletal remains were found.

Identification of the remains solves one part of the nearly 4-year-old mystery, but officials said it is far from clear why the family may have been targeted or who carried it out.

McMahon said there is no information where the family members were killed, adding that there is no indication that the killings were "cartel related."

At the time of their disappearance, Joseph McStay owned a company that built custom water features for high-end commercial businesses.

Summer McStay was a stay-at-home mom to her sons.

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