Two Marines were arrested Thursday on suspicion of killing two fellow Marines whose bodies had been found earlier this week in a burning car in Twentynine Palms.
The suspects, Demitrius McClendon, 20, and Vernon Walker, 20, are stationed at Twentynine Palms Marine Base, as were the victims.
Sheriff's deputies in San Bernardino County are looking for a third suspect in the killings, which they said had stemmed from a drug deal.
On Sunday morning, deputies found the bodies of Julio Chavarrias-Vargas and Angel A. T. Wathen, both 22, in Wathen's burning car at Old Dale Road and Lupine Avenue.
Later that day, police in Rancho Cucamonga discovered a large amount of blood at a loading dock on Rochester Street, sheriff's spokesman Chip Patterson said.
"At that place, we thought two people might have been murdered," he said. "We had two murder victims, along with other physical evidence," Patterson said.
Deputies interviewed Marines who knew the victims, then made the arrests.
"The killings occurred because of a drug transaction that went bad," Patterson said. "All four individuals were involved in buying and selling drugs."
Wathen died from a shotgun wound to the chest, according to the coroner's office.
The cause of Chavarrias-Vargas's death has not been determined.
McClendon's father, Glen McClendon of Fort Wayne, Ind., said his son hadn't been in Twentynine Palms on Sunday, but did not give a location.
"He's clean," McClendon said.