The shootout occurred Wednesday afternoon as Los Angeles County sheriff's deputies attempted to stop a vehicle driven by a woman police described as another former girlfriend of Terron J. Boone. A 7-year-old girl was a passenger along with Boone.
Deputies shouted "hands up!" and Boone opened the passenger door and began firing from a semiautomatic handgun, authorities said. Boone fired at least six rounds, hitting the deputies' vehicles, according to Los Angeles County Sheriff's Lt. Robert Westphal of the homicide bureau. Four deputies returned fire, fatally striking Boone.
The girl and deputies were not injured. The driver was struck by gunfire and treated and released from a hospital.
Boone, 31, was the half-brother of Robert Fuller, 24, who was found hanging from a tree last week in Palmdale.
Jamon Hicks, an attorney for the Fuller family, confirmed Boone's relationship to Fuller but declined to comment further Thursday.
The sheriff's department has not yet identified the shooting victim as Boone.
Fuller was found in a park near Palmdale City Hall early in the morning of June 10. A preliminary autopsy was conducted the next day and the initial finding of suicide immediately prompted skepticism among the black community in an area of Los Angeles County with a racist history.
The coroner's office said Fuller's death appeared to be a suicide and homicide detectives said there was no evidence to the contrary at the scene. That outraged family members who said authorities were too quick with that finding and failed to consider the possibility of foul play. They are seeking an independent autopsy.
RELATED: Officials call for independent probe into death of Robert Fuller
More than 1,000 people turned out for a protest and memorial Saturday around the tree where Fuller's body was found. His family and friends described him as a peacemaker who was street-smart, loved music and video games, and mostly stayed to himself.
The FBI and state attorney general's office on Monday announced they are monitoring the LA Sheriff Department's investigation of the death.
Fuller was the second black man to be found hanged in a public place in Southern California in recent weeks.
Malcolm Harsch, a 38-year-old homeless man, was found on May 31 in Victorville.
In Boone's case, authorities allege he imprisoned his on-and-off girlfriend in her Palmdale home between June 9 and Monday, threatening and pistol-whipping her, court documents show. The girlfriend "waited for an opportunity when he wasn't looking and she was able to get out, run to a business and had them call 911," Westphal said.
RELATED: Robert Fuller Palmdale death: Family, friends gather to demand answers as calls for state investigation grow
Prosecutors filed 13 counts against Boone on Tuesday and a warrant was issued for his arrest. The next day a surveillance team of deputies followed Boone to a residence in the desert community of Rosamond, about 20 miles north of Palmdale.
Boone got in the vehicle and left with the woman and child. Deputies later moved in to arrest him and the shooting erupted.
Westphal said Boone's motive for the kidnapping and assault remain under investigation, as is any potential link between the woman and Fuller.
Boone's criminal record includes convictions on charges of burglary, robbery, corporal punishment or injury to a child, according to the California Department of Corrections and Rehabilitation. His parole ended in November.