The flames started near a dam in Northern California last summer and tore through a vast stretch of land, killing two men whose homes lay in its path.

For eight months, investigators worked to determine the cause of the Markley Fire, which merged with nearby blazes in what became one of the largest wildfires in state history. On Wednesday, authorities announced they had found an answer: The blaze was set intentionally to cover up a killing.

Police arrested Victor Serriteno within weeks of the August 2020 fire, charging him with killing Priscilla Castro, 32, of Vallejo, Calif., who he had met for a date. Prosecutors now plan to file additional murder charges against the 29-year-old in connection to the blaze, including the two men it killed: Douglas Mai, 82, and Leon “James” Bone, 64.

“The fire had devastating impacts on so many people in our community,” Solano County District Attorney Krishna Abrams said during a news conference announcing the findings.

Attached is an important update regarding the August 2020 murder of Priscilla Castro and the subsequent investigation...

Posted by Vacaville Police Department on Wednesday, April 28, 2021

Serriteno appears to have been arrested in 2014 on charges of attempted murder and assault with a firearm. A U.S. Customs and Border Protection news release said Serriteno, a U.S. citizen, was taken into custody after a fingerprint scan revealed the Solano County Sheriff’s Office had a warrant out for his arrest.

It was not immediately clear what happened in that case. Court records suggest he was sentenced to prison in 2015 and released sometime after.

Castro, who had a 9-year-old daughter and dreamed of owning her own salon, was reported missing Aug. 18, the same day the Markley Fire began to burn. Her family hadn’t been able to reach her for two days, police in Vacaville, Calif., said in a news release. Detectives began an “intensive investigation in search of answers” after discovering her cellphone was off and her social media accounts quiet, the police department said.

Investigators learned Castro had come to the Vacaville area from Vallejo for her date with Serriteno, whom she had met online. After that, police said, “Priscilla was not seen or heard from again.”

Cellphone data obtained by police indicated Serriteno had been to the base of the Monticello Dam on the night of his date with Castro, according to the Vacaville Reporter. Detectives searched that area Sept. 2 and discovered a badly burned body later identified as Castro’s. Authorities ruled her death a homicide; they have not publicly revealed a cause of death or motive.

Police tracked down Serriteno in Santa Clara, Calif., and arrested him on Sept. 11. He was booked into the Solano County Jail on a no-bail warrant in Castro’s killing.

As he sat behind bars, the Markley Fire kept burning, becoming part of what California officials called the LNU Lightning Complex Fire. The flames ripped through the hills surrounding Vacaville, Napa and Fairfield, killing six people and destroying almost 1,500 buildings. The fire wasn’t contained until October.

From the start, authorities sought to figure out what sparked it.

“The moment a fire begins burning, there’s an element within Cal Fire that begins investigating how those started,” Solano County Sheriff’s Office Lt. Jackson Harris said during a Wednesday news conference. “And with the scope and size of this fire … unfortunately it just took a little bit of time.”

The sheriff’s office released few details about its investigation, noting that the case is still pending. Abrams said her office is seeking to charge Serriteno with two counts of murder and two counts of felony arson. He’s set to appear Friday in court, where he will be arraigned on the new charges. A public defender is representing him, but online court records do not list a name.

To Castro’s family, this week’s news “just tore the wound open again,” CBS Sacramento reported. Castro’s mother, Lisa Phelps Nunez, told the station she was struggling to accept the circumstances surrounding her daughter’s death.

“You kind of pull anything out of your mind to see her again, or that it didn’t really happen,” she said.

Mai, who served in the Navy and then embarked on a career in law enforcement, was an outdoorsman with a dry sense of humor, his obituary said. He became an assistant Scout master with the Boy Scouts, eager to share his love for outdoor adventures and community.

“He never missed going to the end of the driveway to pick up his paper, returning to a cup of coffee and to work his daily crossword, while the cats walked on his paper and the dog laid at his feet,” his obituary said. “He loved and was loved by all his family and friends, whether lifelong or just meeting in the grocery line.”

Bone, who was visually impaired, often walked miles in the English Hills neighborhood he had long called home. Nathan Guerrero, who grew up in the area, told KCRA he would “always be out on the road walking — big smile, nice wave.” After his death, someone put up a poster on a stop sign near his home that read, “RIP Leon Bone. You were loved.”

Jasmine Castro, Castro’s sister, told CBS Sacramento her family feels for friends and relatives of Mai and Bone.

“We know the pain; we know how it feels to lose someone that you love,” she said. “He doesn’t deserve to get away with not one bit of this.”

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