BILLINGS, Mont. — A Billings man accused of fatally shooting a friend and wounding himself with a military-style AR-15 rifle while the two were tripping on mushrooms has pleaded guilty to negligent homicide.

The Billings Gazette reports 30-year-old William Kenney entered his plea June 28, and prosecutors will ask for a 25-year prison sentence.

Investigators say Kenney told them he and 25-year-old John Smathers “got kinda crazy” and thought they were dying after getting high on psilocybin mushrooms in November. Kenney told them he and Smathers couldn’t handle the effects of the mushrooms anymore, so they decided to shoot themselves.

Kenney shot Smathers, then shot himself and passed out. An autopsy determined Smathers died of a gunshot wound to the back of the head. Kenney had a gunshot wound to his chin.