"We really suspect that there's (dozens) of people that could be victims. He's actually targeting boys," Officer Lisa Holland told Petchenik.
Investigators said Palmer abused some of those students while parents were just feet away.
According to arrest warrants, Palmer told parents to stay outside of his home so that he could have the kids inside. The warrant said he taught the children in a “sound proofed” and locked room.
"It's kind of a classic 'grooming case' where he is a friend with the parents, tries to be friends with the kids and this goes on for years," Holland said.
Petchenik also spoke with a woman who lived up the street from Palmer and asked WSB-TV to conceal her identity.
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She recalled a specific comment that Palmer made to her that in hindsight was concerning.
"“He said something about loving children so much, how he loved the big, fat ones. ‘You just want to squeeze them,’” she told Petchenik.
Palmer was indicted on child molestation charges by a grand jury Tuesday and remains in the Fulton County Jail without bond.