Richmond police said at a press conference Wednesday that they’ve arrested a Richmond man in connection with an arson that killed his father and nephew and critically injured his sister and her daughter, his niece.
Sergio Rivera-Vega, 32, was arrested shortly after officers began investigating the Tuesday night fatal fire, which occurred in the 200 block of 15th Street two doors away from another house fire that was reported about 30 minutes earlier at another residence where the occupants were not home at the time.
Police said that detectives identified Rivera-Vega as the person who set the second fire and took him into custody at the scene while he stood just beyond the yellow police tape.
According to authorities, the earlier fire was set by a woman who was arrested Wednesday morning, though police believe that the incidents are unrelated. They did not identify her.
“At this time we firmly believe that these are two isolated incidents,” said Richmond police Lt. Joseph England. “We have no evidence to believe that our (homicide) suspect was involved in the first fire.”
England said that the first fire is “still under investigation” and that authorities do not know what led to it.
Police Chief Timothy Simmons, who spoke at the press conference on the steps of city hall, said that authorities immediately considered the second fire suspicious due to its proximity to the first fire.
“It occurred a few houses away from the first fire and began within a short period of time while emergency personnel were still responding to the original fire,” Simmons said, adding that there is no longer any immediate danger to the neighborhood as a whole.
The first fire was reported on 15th Street between Macdonald and Bissell avenues at about 8:16 p.m., according to fire officials. About 30 minutes after firefighters put out that blaze, Richmond fire Chief Aaron Osorio said, they noticed smoke coming from a second home and discovered the four people inside. They were taken to the nearby Kaiser hospital.
Osorio said that the second fire prompted a larger response by multiple agencies including the El Cerrito Fire Department and Contra Costa County Fire Protection District.
The victims who died were Rivera-Vega’s father, who was 47, and the suspect’s 5-year-old nephew. The two who were critically injured were the suspect’s 33-year-old sister and her daughter, a 2-year-old girl. His sister is also the mother of the boy who died.
England said that the 47-year-old man died at the scene and the 5-year-old boy died at the hospital. The woman was taken to a Santa Clara burn center while the 2-year-old is at Oakland Children’s Hospital. Both remain in critical condition.
Police said that the injuries sustained by the victims who died appeared to be from the fire though the actual cause of death has yet to be determined.
“Rivera-Vega was subsequently booked in the Richmond Police Department jail on two charges of murder and two charges of arson causing great bodily injury,” Simmons said, adding that Rivera-Vega’s bail has been set at $2.5 million.
Rivera-Vega’s name appears in the Contra Costa County inmate locator, but details of his arraignment have not been released.
Police responded to an assault call on the block 30 minutes before first fire
According to RPD incident reports reviewed by Richmondside, Richmond police were on the same block just before 7:30 p.m., 30 minutes before the fire reportedly started, for an incident involving an assault with a deadly weapon that is not a firearm and criminal threats.
England declined to answer questions related to prior calls at the location and said that detectives are still investigating any previous contact officers might have had with Rivera-Vega.
Simmons said that the scene was an “emotional” one and issued condolences to the families and residents impacted by the deaths.
“This is an absolute unimaginable tragedy,” Simmons said. “It has taken the life of a man and a young child while leaving a woman and another young child literally fighting for their lives. My deepest condolences are with the victims, their loved ones and everyone affected by this devastating incident to include neighbors and this entire community.”
The deaths are Richmond’s sixth and seventh homicides of 2026, according to RPD crime statistics.
This story is developing and will be updated as information becomes available.
Is there a gofundme set up for the surviving victims of this horrific incident? I’m sure I’m not the only neighbor who would like to contribute.