An explosion killed a spa owner Tuesday in a medical office building in California, and police believe it was the result of a deliberate bombing, KCBS-TV reported.
"At this time, we have ruled out the potential for this to be an accident," Orange County Undersheriff Don Barnes said Wednesday.
Authorities currently have no suspects in the crime, but they are investigating the spa owner's ex-boyfriend, who was arrested Thursday after the FBI found an "unregistered destructive device" during a search of his home.
What's the story?
The explosion occurred inside Magyar Kozmetika, a spa in Aliso Viejo, California, owned by Ildiko Krajnyak.
Krajnyak, 48, was killed in the explosion, and two other people were injured but are expected to survive.
Police don't know how the explosive was delivered to the spa, but have confirmed that it did not come through the postal service.
"At this point, our working theory is that this explosion was caused by a device, and although the damage was extensive, there are some components that we have located at the scene that are inconsistent with what one might expect to find at this business," FBI assistant director Paul Delacourt told KCBS.
The investigation so far has included a search of the home where Krajnyak lived with her mother and husband, and the home of Stephen Beal, her ex-boyfriend.
Krajnyak and her husband were going through Chapter 13 bankruptcy, which was closed and dismissed one day before the bombing. They were in debt to a list of creditors and the Internal Revenue Service.
Beal was listed on financial records as the chief financial officer and secretary of a corporation he and Krajnyak formed while she and her husband were going through bankruptcy.
'He used to make rockets'
One of Beal's neighbors said that Beal had a habit of building large rockets.
"He used to make rockets as big as I am, in the driveway by his garage, and he'd go out to the desert [and launch them]," neighbor Mushroom Montoya told KCBS.
Beal, 59, was arrested on suspicion of being in possession of an unregistered destructive device but has not been charged in relation to the spa bombing. The FBI declined to detail what the destructive device was at this time.