Hoaxers often use a computer and programs available online to trick 911 systems into thinking the distress calls are coming from the address where officers are dispatched, even though the prankster may be miles, or several states, away.

Although the use of Internet phone providers can make it harder to track the callers, ‘‘nothing on the internet is ever terribly secret,’’ Smith said. ‘‘There’s always going to be a trail,’’

Spoofing a phone number is legal and used for many legitimate business purposes, but it has become a favorite technique of pranksters to harass strangers or send pizza deliverymen or locksmiths to unwitting targets’ homes.

Dr. John Grohol, a research psychologist who studies internet behavior and founded the online community PsychCentral.com, said the motivation for celebrity swatting may be rooted in the hoaxers desire to impact the stars’ lives and gain notoriety for themselves in online communities.

‘‘You have to kind of look at it from the perspective that most people don’t have a lot of opportunity to affect a celebrity’s life directly,’’ Grohol said. ‘‘This is a way that a person can feel empowered.’’

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