Joshua Lee Simmons and Dennis Eugene Vance were taken into custody for the murder of Javonnta Marshann Murphy, the Los Angeles County Sheriff's Department said in a statement.
Murphy's body was discovered on July 31. Days later, the county coroner's office said his cause of death was a gunshot wound to the head.
Simmons, 37, and Vance, 41, were arrested on Oct. 3 and arraigned two days later, authorities said. Simmons was also charged for an attempted robbery at an El Monte jewelry store on Sept. 2.
Heartbroken family seeks justice after man's body found in barrel in Malibu
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Authorities say Simmons is the same suspect who was captured on video trying to rob a family-owned jewelry store in El Monte. The owners of Meza Jewelry ended up beating him and pulling off his shirt.
Simmons was charged with murder, personal use of a firearm and criminal threats. He also faces additional charges of attempted robbery, criminal threats and personal use of bear spray in connection with the attempted robbery.
Vance was charged with one count of accessory-after-the-fact in connection with Murphy's death.
Both suspects "are known to be acquaintances of the victim," the Sheriff's Department said.
The motive for the killing remains unknown, investigators said.
Anyone with information about the case is urged to call the sheriff's Homicide Bureau at (323) 890-5500.
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