Sheriff's officials say an 8-year-old Northern California girl who they say was sexually assaulted and killed by a teenage neighbor died of asphyxiation and stab wounds to the neck.

Santa Cruz Sheriff's Lt. Kelly Kent revealed the results Thursday of an autopsy of Madyson Middleton.

Fifteen-year-old Adrian Jerry Gonzalez is charged with raping and killing Madyson and hiding her body in a bin. Both children lived at the Tannery Arts Complex with their mothers and were acquaintances.

The death and arrest have shocked the close-knit artists' community.

Police say the teen lured Madyson into his family's apartment. Once inside, he tied her up, then sexually assaulted and killed her, according to a charging document.

Gonzalez is being prosecuted as an adult. He faces life in prison if convicted.