Martinez is sitting in an Alabama jail, facing murder charges there. Police in Alabama say he has confessed to at least 30 murders throughout the United States, including 11 here in California alone.
Martinez was born in Fresno and recently lived in Delano.
He's also been tied -- by a DNA match to a cigarette butt found inside a victim's truck -- to a 2006 double homicide in Ocala, Fla.
Martinez explained to investigators that his record of violence has to do with his job as an enforcer for Mexican drug cartels. He claims he'd be called when someone hadn't lived up to their obligations.
Action News will have a camera crew at the morning news conference in Tulare County, and we'll provide updates throughout the day on this breaking story.