A person called the Alameda County Sheriff's Office Thursday night and said someone had three hostages and an assault rifle and demanded $15,000 or the hostages would be killed, according to sheriff's officials.
The call came in at 8:47 p.m. and the caller said the hostages were being held at a home on Grove Way in Castro Valley.
But sheriff's officials suspected the report might be a "Swatting" call.
According to sheriff's officials, "Swatting" is a trend in which someone calls law enforcement to report a violent crime in progress at an unknowing person's home or business. The caller provides details of the crime and comes across as real in order to get a response from law enforcement.
Sheriff's officials said similar demands and threats were directed at the same home in Castro Valley last year. They determined that a former resident was being targeted after having a dispute with others while playing video games.
Deputies determined the scene at the home was safe and no one was injured or inconvenienced, sheriff's officials said.
Deputies are investigating the case and have not yet identified the person who made the fake call.
Sheriff's officials said pranks such as this have been associated with internet gaming as a way to get back at a rival. It's illegal and extremely dangerous, according to sheriff's officials.
A recent "Swatting" hoax in Kansas resulted in the death of an innocent man.
Sheriff's officials said this is a good time for parents to talk to their children about online gaming safety.