A woman's head was severed with a sword in San Carlos Thursday, authorities with knowledge of the investigation told NBC Bay Area's Investigative Unit.
The suspect, who returned to the scene, was arrested in connection with the woman's death, according to the San Mateo County Sheriff's Office. The suspect was later identified as Jose Landaeta Solano.
Deputies near the intersection of Laurel Street and Magnolia Avenue were flagged down at about 11:50 a.m. by witnesses who reported an assault in progress, the sheriff's office said. When deputies arrived at the scene, they found the woman dead.
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San Mateo County Sheriff's Office Lt. Eamonn Allen said during an afternoon media briefing a "stabbing instrument" was used, but he did not provide further details as the weapon is still outstanding.
"Anytime someone loses their life, it's certainly a tragedy," Allen said. "As far as the shocking nature of it, I do know that the deputies that first arrived on scene were a little beset by the scene. We are providing them peer support. We are also providing support for the witnesses that were on scene as well because there were several civilian witnesses."
Chapele Thorborne, who lives in the neighborhood, told NBC Bay Area Thursday that he was in disbelief.
“It was kind of a shock, you know. This is a nice neighborhood. So, it’s a shock,” he said.
Thorborne said that he knew both the victim and Solano, and added they moved into the neighborhood about three years ago.
“They seemed like they loved each other,” he said.
Investigators told NBC Bay Area that Solano has an extensive, violent criminal past and a history of mental illness.
“When our deputies responded to the scene and started to process the scene, it's my understanding that he was contacted in the area, but he was not in the immediate scene,” Allen said.
Solano was then taken to the hospital for what police said was "some kind of medical emergency."
The victim has been identified by her father as 27-year-old Karina Castro. NBC Bay Area was told she had two children, a 7-year-old and a 1-year-old.
Investigators are still looking for the weapon described by some as a samurai sword. They also said there is a history of domestic violence calls and other complaints tied to the home.
Anyone with information about the incident is asked to contact Detective Brandt with the sheriff's office at 650-333-8195 or dbrandt@smcgov.org.