WASECA, Minn. (AP) - An expert for the prosecution has testified that a teenager accused of plotting to attack his southern Minnesota school poses "a significant risk for future violence."

Tuesday's hearing is to determine whether the 18-year-old from Waseca should be tried as an adult or remain in juvenile court. He was 17 when he was arrested last year.

Waseca police say they found him in a storage unit with bomb-making materials and a plan to kill his family and attack his high school.

Attempted murder charges against the teen were dropped. He still faces charges for possessing explosives.

Reports say psychologist Katheryn Cranbrook testified the teen has mild to moderate autism and is focused on violence. Cranbrook recommended adult certification.

The teen remains at a juvenile facility in Willmar.