The bones of four people were found in two shallow graves in Southern California's Mojave Desert, but it will take more investigation to determine who they are and how they died, authorities said Wednesday.
Sheriff's homicide detectives and coroner's officials wrapped up a three-day excavation in barren scrubland on the outskirts of Victorville, the San Bernardino County Sheriff's Department said in a statement.
"There were two graves where remains were located as well as additional skeletal remains ... near the graves," the statement said.
A third site that appeared to show some disturbed ground also was dug up but investigators determined it was unrelated to the gravesites.
Authorities went to the site near the Interstate 15 freeway on Monday after an off-road motorcyclist reported finding bones that coroner's investigators later confirmed were human.
"It does appear that they have been out there for an extended amount of time, but as you know, anything that stays out in the desert for a period of time deteriorates fairly quickly," Randy Naquin, spokesman for the San Bernardino County Sheriff's Department, told KPCC.
A forensic anthropologist will work to determine the age and gender of the remains.
"It is difficult at this point to state how long it will take to determine the causes of death," sheriff's spokeswoman Jodi Miller said.
Victorville is in the high desert about 60 miles northeast of Los Angeles. No homes or businesses are near the gravesite.