A Mukilteo teen, who endangered a California family when he hacked into a 911 emergency call system, left electronic evidence that suggests he did something similar in three other states, a spokeswoman for the Orange County District Attorney’s office said Thursday.

On Wednesday, Randall T. Ellis, 19, pleaded guilty to five criminal charges and was sentenced to three years in a California prison.

Ellis admitted placing a phony 911 call from his home in Mukilteo that led a SWAT team, police dogs and a helicopter to converge on a home and innocent family in the city of Forest Park in Orange County.

Inside their California home, a couple and their two toddlers were sleeping. The man was awakened by a noise, thought there were prowlers outside and grabbed a kitchen knife to carry for protection. When he checked the back yard, he found SWAT team deputies pointing assault rifles at him.

The man and his wife were handcuffed until authorities determined the call was a hoax.

“That very easily could have turned deadly,” said Farrah Emami, spokeswoman for the Orange County District Attorney’s office. “We were very fortunate.”

Emami said her office and the sheriff’s department used a new high-tech lab and computer system to track down Ellis through cyber “fingerprints” left by his hacking. In the examination of Ellis’ computer, Orange County officials found evidence that he did something similar in Washington state, Pennsylvania and Arizona.

Emami said there’s no indication that other jurisdictions have evidence to prosecute Ellis for making false emergency calls.

The technology enabled the Orange County Sheriff’s Department to “capture that information in a timely manner and link Mr. Ellis to this crime,” Emami said. “He hacked into the 911 system in Orange County. We have not released how he did that.”

What he did was “set in motion deliberately all these events that led to a family being held at gunpoint,” Emami said.

Ellis pleaded guilty to five felony counts, including computer access and fraud, false imprisonment by violence and falsely reporting a crime.

In addition, he will have to pay $14,765 in restitution, most of which will go to Orange County’s sheriff’s department. Mukilteo police will get about $700 for their expenses.

Investigators believe the incident began when Ellis called the couple’s home while they slept about 11:30 p.m. on March 29. The woman answered the phone and told the unknown caller that he had dialed the wrong number.

The caller insisted he had the right number and then made lewd comments. The woman later told police it sounded like the caller was typing during the conversation.

Detectives believe that Ellis was confirming the couple’s name, according to the search warrant.

A short time later, detectives believe Ellis used his computer to call 911 dispatchers. They were given the Orange County couple’s address and were told that a woman was going to be shot.

Ellis was arrested in Mukilteo in October and has been jailed since.

Reporter Jim Haley: 425-339-3447 or jhaley@heraldnet.com.