First it was believed to be a bomb, then it was dismissed as a freak industrial accident, and now authorities are again saying that the explosion last week near a Santa Monica synagogue was, most likely, deliberately planned.

Part of the confusion, authorities say, was connected to the device itself: An explosive layered under hundreds of pounds of concrete poured into a trash bin is not something bomb technicians typically encounter.

“This is clearly not a traditional type of explosive device,” said FBI spokeswoman Laura Eimiller. “Clearly if it were, our investigators would have been able to identify it immediately.”

Thursday’s blast sent a 300-pound metal pipe encased in concrete crashing through the roof of a home next door to Chabad House on 17th Street, near Broadway. Authorities are now searching for a homeless man they believe to be connected to the explosion.

On Friday, investigators released a photograph of Ron Hirsch, 60, who had been known to frequent Jewish centers in the area looking for charity. Hirsch, also known as Israel Fisher, should be considered “extremely dangerous,” authorities said.

On Saturday, area residents said they didn’t know what to think of the incident.

Janti Rashti, 59, whose home was damaged when the concrete mass fell on her rooftop, said the incident has been an emotional roller coaster. Her first thought: “Was it going to happen again? The police didn’t tell me anything, the Fire Department didn’t tell me anything.”

But on Friday, investigators interviewed her and showed her 16 photos. Among them was one of Hirsch, she said, whom she recognized as a man who sometimes slept by the side of the synagogue. “I just don’t believe it was him,” Rashti said. “The synagogue was never mean to him. I certainly never did anything to him.”

She described Hirsch as a quiet man who never waved, never said hello, never spoke with anyone.

Authorities said Hirsch has been linked to the explosion by items found at the scene. A motive is still unclear. In the meantime, his photo has been distributed, and neighborhood residents are on the lookout.

John Fasce, 60, a homeless man in the area, said he had seen Hirsch before. Two men sitting nearby, smoking, said they, too, recognized him. “If I see him,” Fasce said, “I’m calling 911.”

After initial word Thursday morning that the explosion may have been caused by a pipe bomb, authorities seemed confident that it was a freak industrial accident.

At one point, one official told the media: “We’re absolutely positive it was not a terrorist act.”

Eimiller said it’s common to hope that an investigation will identify accidental causes. “It can happen when terrorism is suspected. Everybody hopes it’s a Code 4,” she said, referring to police lingo for “all clear.”

However, she said, that desire does not get in the way of the FBI’s bomb technicians objectively parsing the evidence to arrive at an accurate assessment.

Later Thursday authorities began uncovering evidence indicating the explosion was deliberate, and by Friday morning they had decided to go public with that information.

“This was a huge mechanism with construction-type materials that were painstakingly taken apart by experts. That developed new evidence,” Eimiller said. “Some of the evidence was confined in solid cement. Hundreds of pounds of materials were investigated throughout a 24-hour period.”

(Source: LA Times)