A Washington state teenager is facing 18 years in prison on charges that he used his PC to access Orange County, Calif.'s 911 emergency response system and convinced the sheriff's department into storming an area couple's home with a heavily armed SWAT team.

Randall Ellis, 19, of Mulkiteo, Wash., is not only facing charges of unauthorized computer access, but he's also facing assault charges by proxy, meaning that authorities want Ellis to be convicted as if he, and not the SWAT (Special Weapons and Tactics) team, pointed weapons at the victims.

The incident took place late in the evening of March 29, when Ellis allegedly used his computer to call the Orange County 911 dispatch and, during the course of a 38-minute telephone conversation, convinced dispatchers that he had murdered someone on the premises and was about to do it again.

Within minutes, fire, police. and a helicopter team had been dispatched to the home of the Lake Forest, Calif., couple, whom authorities declined to identify.

"They surrounded the home, inside were a husband and wife and their two toddlers," said Farrah Emami, a spokeswoman with the Orange County District Attorney's office. "The husband heard rustling outside of his home and believed it to be a prowler. He took a knife and went into the backyard. Instead of finding a prowler, he found a SWAT team pointing assault rifles at him."

"It really easily could have escalated into an innocent person being killed," she added. "We're lucky that they didn't shoot him."

Emami characterized Ellis as a "computer hacker," but declined to explain exactly how the attack was carried out. "One of the reasons that we're not disclosing exactly how he did it is because we don't want to teach other computer hackers how to do it," she said.

Still, it's not clear that Ellis's alleged hack involved anything more complicated than tricking the 911 system into thinking he was calling from the Lake Forest couple's number. County officials said Wednesday that he did not exploit a technical flaw in the 911 system's software.

The technique that Ellis used "doesn't require any special skills," said Jim Amormino, a spokesman with the Orange County Sheriff's Department. "The way he did it: I am not computer savvy, but I can do it."

The March 29 incident cost the county an estimated $18,000, Amormino said.

Low-cost calling card services such as SpoofCard have been available for years, allowing customers to make it appear that their calls are coming from any number they wish.

In June, four people were charged in Texas with operating a chat line where they taught people how to make false 911 calls, sending emergency response teams to targeted victims, a practice known as "swatting." In a June 12 swatting incident, a swatter called up Cleburne, Texas's 911 dispatch using a commercially available spoof card and Skype, then "stated that he had shot and killed members of the family, that he was holding hostages, that he was using hallucinogenic drugs, that he was armed with an AK-47, and he demanded $50,00 and transportation across the U.S. border to Mexico," according to court filings.

Authorities said that Ellis had made nearly 200 fake 911 calls to dispatch systems in California, Arizona, Washington, and Pennsylvania.

He is set to be arraigned Monday in Santa Ana, Calif.