They believe Juan Osornio Martinez killed Irma Campos in a domestic dispute last Friday at a home on Whitton Avenue.
Martinez is homeless and is known to spend a lot of time in San Jose area.
In the last week, there's been a murder and two fires at that same home in the 1200 block of Whitton Avenue. The fires happened early Sunday morning just hours apart.
If you have information on the fires or know where Martinez may be, you're asked to call San Jose police.