Pennsylvania ? A troubled teenager accused of plotting a school attack built up a stash of weapons with the help of his mother, authorities said Friday.

Michele Cossey, 46, was arrested Friday on charges of illegally buying her home-schooled son, Dillon, a .22-caliber handgun, a .22-caliber rifle and a 9 mm semiautomatic rifle with a laser scope.

The parents were indulging the boy’s interests because he was unhappy, not knowingly aiding a school assault, Montgomery County District Attorney Bruce Castor said. The parents didn’t know of the teen’s plans, but “by virtue of her indulgence, she enabled him to get in this position,” Castor said.

Authorities have said they do not believe an attack was imminent and are not even certain one would have occurred.

“This was a smart kid that clearly believes he was picked on and was a victim,” Castor said. “He had psychological issues and began to act out on those feelings.”