Skittish even at the best of times, homeless people in Orange County have been running to shelters this week in search of a safe place to sleep after the separate stabbing deaths of three homeless men. The authorities believe there is a serial killer stalking the homeless.

Demand for beds at some shelters was up as much as 40 percent in the last couple of days, while other shelters have been inundated with calls from frightened homeless people wondering if the killer has been caught, whom he is targeting and where they can go.