San Marcos fire victims ID’s as married couple in 70s; accused killer due in court

A husband and wife in their 70s killed in a suspected arson fire at their house in San Marcos have been identified by officials, with their accused killer expected in court on Thursday.

The two victims have been identified as 73-year-old Michael Austin and his Kathryn Austin, 72. Luis Alvarado, 33, a tenant living in their home on the 900 block of Lacebark Street, near Fulton Road and Woodland Parkway, is expected to be arraigned at the Vista courthouse on murder and arson charges.

The man arrested by San Diego sheriff’s deputies over the weekend for allegedly killing two people in a San Marcos house fire has a history of violence involving a past landlord and roommates, according to court documents, reports NBC 7’s Allison Ash.

First responders arrived at about 11:45 p.m. Saturday after reports regarding a residential fire, according to the San Diego County Sheriff’s Office.

By the time firefighters arrived, the house was engulfed in flames.

The bodies of the Austins were found after firefighters extinguished the fire at the two-story home, homicide investigators said Sunday.

“While working to put out the blaze, firefighters located two deceased individuals inside a second-floor room,” Marquez said in a statement on Sunday. “The San Marcos Fire Department requested the sheriff’s bomb/arson unit to conduct a full investigation into the cause and origin of the fire.”

SUSPECT’S CRIMINAL HISTORY

There were two criminal cases pending against Alvarado in North County at the time of the fire, according to court papers. Those cases had been merged and his charges were suspended pending the outcome of a mental health diversion plan.

Alvarado was in court just weeks ago, on March 13, when his public defender reported Alvarado was taking his meds (olanzapine), was seeing his doctor regularly and was managing his mental illness.

According to WebMD, the antipsychotic Zyprexa, the brand name for olanzapine, is commonly prescribed for schizophrenia and bipolar disorder.

The San Diego County Homicide Unit has arrested a man in connection with a deadly residential fire in San Marcos on Sunday. NBC 7 has more on the arrest and criminal charges. 

That diversion plan was put in place in May 2025 after Alvardao was named in a pair of criminal cases “and has been before the court for review hearings multiple times over the last year,” San Diego County District Attorney spokeswoman Tanya Sierra told NBC 7 on Monday.

Details of those cases include:

In October 2024 in Oceanside, Alvarado allegedly threatened his three roommates with a kitchen knife. According to court documents, he threatened to kill them: “Defendant put the tip of the knife within a few inches of [name deleted] face and started yelling about ‘gang stuff’ and that he ‘has bodies.’ ”

And then, on Jan. 15, 2025, Alvarado was arrested after allegedly assaulting a man in Carlsbad. According to court papers, that incident began when a woman who rented an apartment to Alvarado found out he had a criminal record and asked him to move out. After the landlord went to court for a restraining order against Alvarado, he showed up later the same day and punched a man in the eye who was there to protect her. Although the victim did not press charges, Alvarado was charged with making threats, allegedly in French on the Facebook messaging app.

The threats were translated into English by prosecutors and reportedly said, “One day I’ll make you cause pain and your death f—ing goose. F– you f—ing. I won’t forget [your] home. F– the FBI.” Alvarado also allegedly sent an image of two bombs and another of a handgun. He is also accused of texting her, “You’re not even going to feel it when I dry you and peel your f—ing skin off.”

According to court documents, Alvarado suffers from “schizoaffective disorder, bipolar type” and is being treated by a psychotherapist.

Before the events of this weekend, Alvarado had been scheduled to go back to court in July to check-in to see if the diversion plan was working.

“While not commenting on this case, the current mental health diversion law provides few legal grounds for DAs to oppose, and the law is not balanced with public safety,” Sierra also emailed NBC 7 on Tuesday. “This is why the district attorney is actively supporting legislation that is pending in Sacramento to change the law so that DAs can make effective legal objections that better protect victims and community.”

Anyone with information regarding the fire or suspect was urged to call the sheriff’s homicide unit at 858-285-6330. Calls made after business hours can be directed to 858-868-3200. Tipsters who prefer to remain anonymous can call Crime Stoppers at 888-580-8477.

With reporting by NBC 7’s Allison Ash — Ed.