HAMILTON, Mont. -

In the wake of the arrest of 18-year-old Adam Michael Chambers, Hamilton schools are reviewing and updating safety plans.

Chambers is an Alternative Learning Center student in Hamilton, who allegedly made threats to shoot students at Hamilton High's graduation Sunday.

Hamilton High Principal Dan Kimzey said he, the superintendent and board members have been in discussion.

A court report said Chambers admitted "making threats while in the company of others."

The report said Chambers expressed "an extreme hatred" for Hamilton High students, had been depressed for months, and planned to use his father's AR-15 at the ceremony.

"Some of the people that were around took it seriously enough," said Kimzey, "and had the courage to repeat it to a parent who had the good sense to call law enforcement Sunday morning."

Kimzey describes Chambers as a "smart kid," who had played football and had an interest in speech and debate. He said the boy was pleasant in his interactions, and in talking to his dad, there had been some issues of bullying.

The court report said Chambers had tried to check himself into an adult crisis facility in Hamilton, but was refused admittance.