CENTENNIAL, Colo. (AP) — Investigators plan to release updated information about a shotgun attack on a suburban Denver high school that fatally wounded a 17-year-old girl.

Arapahoe County Sheriff Grayson Robinson scheduled a news conference for Monday morning on the Dec. 13 shooting at Arapahoe County High School.

Claire Davis, a senior at the school, was shot point-blank in the face. She died Dec. 21 after spending eight days hospitalized.

Authorities say another Arapahoe High student, 18-year-old Karl Pierson, shot Davis and then took his own life as a deputy sheriff closed in.

Robinson says Davis appeared to be a random victim and that Pierson probably intended to track down a librarian who had disciplined him.

The sheriff says Pierson also had a machete and Molotov cocktails and likely wanted to hurt many others.