(LOS ANGELES) -- A Southern California man has been arrested on suspicion of having an unregistered destructive device amid the investigation into the explosion that killed his ex-girlfriend at the day spa she owned, according to the FBI and a criminal complaint.
But Stephen Beal, 59, has not been charged in connection with the Tuesday explosion that killed his ex, 48-year-old Ildiko Krajnyak, who was also his business partner, and injured three people, federal authorities cautioned.
Inside the Aliso Viejo, California, crime scene, agents said they found items consistent with an explosive device: a 9-volt battery, a cellphone, loose wires melted material that appeared to be duct tape, according to the criminal complaint against Beal.
Injured victims saw the Krajnyak pick up a box in a pile of mail and open it, after which it exploded, according to the complaint.
During the investigation into the explosion, officials served a search warrant at Beal's Long Beach, California, home. Multiple explosive materials were found in Beal's home, including at least three containers of black powder, a 7-foot-tall rocket, rocket-making equipment, two containers of potassium perchlorate -- used as a precursor -- and two containers of red gum, which is used as fuel and binder in fireworks, according to the complaint.
Altogether, 130 pounds of explosives/precursor material were found in his home, more of which was discovered in the garage, the complaint states.
Beal appeared to have rented space in the building with Krajnyak, according to the criminal complaint.
Beal is making his first appearance in U.S. District Court in Santa Ana this afternoon.
The crime scene at the day spa has been rendered safe after the blast sent plumes of white smoke into the air and debris flying into the parking lot.
While evidence collected from the blast suggests that the incident was intentional, the exact means by which it was carried out has not yet been determined, according to the complaint.
The family and friends of Krajnyak are in "complete shock," Irene White, a friend of the family, told reporters Wednesday on the family's behalf.
"Families always came first for Ildiko," White said. "She took great pride in finding beauty in everyone. At this time our family and friends would like to privately mourn a mother, a wife, a daughter and a friend."
White said the family is hoping to get answers.
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