BREESE, Ill. (AP) — A southern Illinois sheriff says a suspect is in custody in the beating death of a high school senior at a party. Clinton County Coroner Phillip Moss says 18-year-old Jacob J. Arter died early Sunday at a hospital in Breese. Moss performed an autopsy on Arter yesterday, but declined to offer specifics as to how the 18-year-old died. Clinton County Sheriff Doug Maue says a juvenile male is in custody. The sheriff’s department is investigating with the coroner and Clinton County prosecutors.