A Fourth of July gathering in San Jose ended in tragedy when 32-year-old Joselyn Martinez was shot and killed on July 5, 2026. A mother of five, Martinez was attending a party when gunfire broke out; the scene left family and neighbors reeling and prompted an immediate investigation.

Police focused on Martinez’s 25-year-old boyfriend, Diego Ulisses Diaz. A neighbor reported Diaz saying he had shot his girlfriend, surveillance video showed him fleeing the scene, and officers arrested him. Authorities also allege he damaged a police car during his apprehension. As a convicted felon, Diaz was prohibited from possessing a firearm, and he was charged with murder and multiple firearm offenses.

The killing was recorded as San Jose’s 14th homicide of the year. Does anyone have information about Joselyn, the party that night, or what led up to the shooting?