CINCINNATI (AP) — A teenager accused of making a hit list and Arvin Robertsplanning a mass killing at a high school near Cincinnati pleaded guilty Thursday to reduced charges of inducing panic.

Prosecutors dropped a charge against the 14-year-old, leveled in February, of conspiracy to commit aggravated murder. He will be sentenced in July.

Hamilton County Prosecutor Melissa Powers said the teen had exchanged text messages with a Colorado man about gassing the school and killing students and staff members. Prosecutors decided against charging the man because he had no ability to take part in the plan.

The county public defender’s office said shortly after the teen’s arrest that he had significant mental health challenges and that he was impressionable.

Powers said the teen had a hit list with the names of at least eight students and one teacher. The boy was arrested after he told another student about the plan, investigators said.