Aaron Gaudinier, 47, was arrested on Thursday.
Investigators say they found several thousand sexually-explicit images and videos of children inside the home he shares with a relative. A least one computer, several boxes of CDs, hard drives, a digital camera, and a small amount of marijuana were seized from the home, investigators said.
A small pile of adult and children's underwear was also seized, they added.
"That's an automatic red flag. And that's where you have to... then that takes your investigation to a whole higher level," said Erica Stuart, Madera County Sheriff's Department Spokeswoman.
A tip earlier this month prompted the investigation. Gaudinier was taken into custody after a search warrant was served at his home on Thursday morning.
Investigators do not believe at this point that Gaudinier appears in any of the photos or videos that were seized, Stuart said.
Those who live nearby told CBS47 on Friday that they're disgusted by the allegations against Gaudinier.
"I'm kinda shocked in a neighborhood like this that it would happen. Especially so close to our elementary school," said neighbor Nellie Uribe, who has four children.
"We do need to get to know our neighbors a little bit better. A lot better," said neighbor Gerianne Storelli.
As of early Friday evening, Gaudinier remained in jail on $5,000 bond.
Records show he was previously arrested on a burglary charge in 1994.