A rabbi spotted 60-year-old Ron Hirsch after he walked into the synagogue saying he needed a meal and a place to stay. He said things didn't seem right, but he still fed Hirsch and put him up in a motel.
Then he called the FBI.
Hirsch is suspected of setting off a pipe bomb outside the Chabad House Lubavitch of Santa Monica on 17th Street on Thursday. He also goes by the names "Israel Fisher" and "J. Fisher."
Los Angeles County prosecutors charged Hirsch with four felony counts Tuesday after an FBI affidavit was filed in federal court saying a receipt for a large amount of chemicals had linked him to the crime.
The state felony counts against Ron Hirsch, 60, include possession of a destructive device near a public place and private residence, explosion with intent to murder, and use of a destructive device and explosive to injure or destroy. He faces up to life in prison without the possibility of parole if convicted, the Los Angeles District Attorney's office said.
A key piece of evidence, a shipping label receipt for the explosives, is linking Hirsch to the bombing.
According to an FBI affidavit, it was the receipt at a box at the scene of the explosion that linked them to Hirsch.
Court papers show the receipt for three 11-pound bags of a demolition agent from Constar Supply, a Northern California construction and industrial supply company.
The package was shipped to Hirsch to a commercial shop in Santa Monica just a few blocks from the synagogue.
Authorities said they found those empty bags, as well as duct tape and bags of cement near the receipt.
According to the FBI, Hirsch boarded a Greyhound bus bound for New York. There were at least 10 destinations between Los Angeles and New York, and after looking through surveillance recordings, investigators spotted Hirsch getting off the bus in Denver.
Surveillance cameras in Denver then showed him buying a ticket for another eastbound bus. Authorities say he has family in New York.
The explosion damaged a wall and sent a 300-pound chunk of concrete with a metal bar attached into the air. The projectile went through the home of Janti Rashti, who said she had seen Hirsch in the neighborhood as a transient.
"I still can't imagine that he would do it," Rashti said. "He was here for two years and nothing happened."
Authorities said the bomb was constructed by filling a pipe with an explosive and setting it in concrete inside a trash can. Police first thought it was an industrial accident, but they later determined the blast was the result of a pipe bomb.
The motive for the blast remains unknown, but it is not being investigated as a hate crime.
Hirsch is scheduled to make a court appearance in a Cleveland federal courthouse Wednesday afternoon. He is then expected to be extradited to Los Angeles.
The Associated Press contributed to this report.