An explosion rocked a Southern California medical office building Tuesday, killing a woman and injuring three other people, authorities said.
Orange County Undersheriff Don Barnes says the formal identification of the body is continuing Wednesday but authorities believe it is that of Ildiko Krajnyak (IL-di-koh KRY-nyak), a licensed cosmetologist.
From a Sheriff's Department news conference at noon: The victim was IIdiko Kranjnyak, 40, who owned the day spa in the building. It is "premature to speculate on the nature of the components of the device", he said.
The official was briefed on the investigation but wasn't authorized to discuss the matter publicly and spoke to the AP on condition of anonymity.
The explosion Tuesday badly damaged a two-story building in the city of Aliso Viejo and injured three other people, including two who remain hospitalized.
Bomb technicians from the Orange County Sheriff's Department, the Federal Bureau of Investigation and other agencies were investigating, said Paul Delacourt of the Federal Bureau of Investigation.
"We can not say exclusively this explosion was intentional", Mr. Sawyer told NPR.
"Investigation is in early stages", the department tweeted.
The blast, which blew out almost the entire first floor, sent plumes of white smoke into the air and debris flying into the parking lot. Tony Bommarito, a spokesman for the Orange County Fire Authority.
"And the ground shook", he said.
"We have not found any type of specific device inside of the building right now that would tell us or lead us to exactly what the device was, if there was a device", sheriff's Cmdr. Official list of victims, the name of the person of interest in the case and technical data on explosive device used is still unavailable to the press. The other woman was bleeding from her head.
Neighbors said there was a lot of action overnight at the property, with 50 or more law enforcement officers descending on the quiet neighborhood and began to investigate.
Two survivors had critical injuries "that were consistent with an explosion, but not necessarily consistent with a bomb", said sheriff's department spokeswoman Carrie Braun.
Officials say other potential causes such as a gas leak have been ruled out.
The ground shook and it felt "almost like an natural disaster, but a big earthquake", a witness in a nearby building told CNN.
A third person suffered smoke inhalation, fire officials said.
One woman, who had burned skin peeling from her arm, said, "Take care of my mother", McWilliams said.
Late Tuesday afternoon, NBC4 - citing unnamed federal sources - said investigators had determined that the blast was an "intentional detonation", and the explosive device was delivered to the building, addressed to a specific person. "Anytime you're near this or you see it, it's going to affect you".
By mid-afternoon, officials said they did not believe there was any further threat to the community.
Authorities provided no additional information about the search.
Authorities initially indicated a vehicle had crashed into the building, but Bommarito said later that did not appear to be the case.