JACKSONVILLE, Fla. -- A 50-year-old man is arrested on child pornography charges after police say they've found thousands of inappropriate photos inside a Jacksonville home.

Police said they were even surprised by how much child pornography federal agents discovered inside Robert Bricker's Northside home.

Investigators said they were tipped off to the alleged crimes during an online chat with the suspect.

"It's really surprising to me because I didn't know this," said Bricker's neighbor, Claudia Bryant.

Bryant said she had no idea that Bricker, who lives right across the street, is in police custody.

Investigators said they seized 7,000 images of child pornography from inside his home.

They said Bricker was downloading and distributing mass quantities of sexually explicit images of children over the Internet -- a secret that Bryant told Channel 4 she never would have guessed.

"I've got children -- nieces and things -- coming around here," Bryant said.

Police said that collecting child pornography was not a new hobby for Bricker. They said they found DVDs with images dating back to 2005.

According to investigators, Bricker used the name "stratocon" on the Internet. They said they started their investigations after he sent child porn to an undercover federal agent in Seattle, Wash.

"I am a father, and this is really disturbing to think that there are grown men that you never know who it is or who they are that would do this for their own pleasures and fantasies," said Jacksonville Sheriff's Office spokesman Ken Jefferson.

For Bricker's neighbors, the accusations against the 50-year-old are a frightening reminder that you may not know what's going on behind closed doors.

"It's made me just think about what can happen next door to you, and that's just right across the street. It's pathetic," said another neighbor.

A federal grand jury indicted Bricker on 10 charges.