The discovery was made Tuesday at the home in the 8000 block of Oakhurst Place after neighbors called police about a man shooting a gun into the air in his front yard. When police arrived, they took 46-year-old William Hunziker into custody and conducted a search of the home. They found Hunziker's elderly mother inside the residence. Authorities said she was in very poor health and was taken to a hospital for treatment.
A bomb squad was called in and several homes in the neighborhood were evacuated after detectives also found bomb-making materials. Pack-rat conditions slowed down the process for investigators.
"They're kind of a hoarder-type situation in the house, so obviously when you have potential explosive materials and devices could potentially be in there, and you have many, many items in there, they have to systematically go through each item," said Det. Guy Toussaint with the Riverside Police Department.
It was also learned Thursday that the officers who initially responded to the home were able to immediately identify the material as explosives because they had recently undergone training by the bomb squad. Authorities are now preparing to fully enter the home.
"We've done I think up to nine self-detonations to render the place safe," said Christian Hoffman with the Bureau of Alcohol, Tobacco and Firearms. "...Once that's done and all the explosives are rendered safe, now we can move to the second phase of the operation, which is actually searching the residence. We have to go through there and we have to look for potentially hazmat situations that are in the house also."
Meanwhile, Hunziker was in a Riverside courtroom Thursday facing several charges related to firing his weapon, along with elder abuse.
Hunziker is facing multiple charges and more could be filed as bomb technicians sort through the explosives and other weapons found inside the home. If found guilty, he could face up to five years in prison. He is being held on $1 million bail.
Oakhurst Place is shut down as bomb technicians go about carefully neutralizing some of the dangerous explosive material. At least five homes near Hunzkier's residence were evacuated.
"There are a number of things in that house that we believe to be high explosives, some hazardous materials as well," said Riverside Police Chief Sergio Diaz. "What's happening today is we plan to do, this morning, a controlled disposal of some of those materials."
Residents say Hunziker has been acting erratically for more than a decade and has been getting progressively worse. Neighbors say he was paranoid, and it was not unusual for him to answer his door armed with a gun.
"There's periods where he'll be normal, and then he'll just go off the deep end, drive his car up and down the street all crazy," said neighbor Rich Gardner. "He's just not normal."