On September 22, 2023, at approximately 8:37 a.m., the Grant County Sheriff’s Office was contacted
about a suspect threatening to harm individuals currently at school in Grant County area high schools
(Potosi, Cassville, and River Ridge). Due to the specific threats made to specific individuals, deputies
immediately took steps to ping the suspect’s phone to see if he was in the area. It was determined he
was several hours away, but alerts were sent statewide to law enforcement agencies attempting to
locate (ATL) the individual making the threats. Although the subject was not in Grant County, the
Sheriff’s Office sent at least one law enforcement officer to each of the schools.
Shortly after the ATL was sent, authorities in Dane County, WI, located a vehicle occupied by Jonah A.
Riley, age 19 of Madison, WI, the suspect in this incident. Law Enforcement conducted a traffic stop on
the vehicle and took Riley into custody. Riley was arrested on multiple outstanding warrants through
Grant County and charges are pending for the threats to the individuals here in Grant County. Riley was
transported to Iowa County, where a Grant County Deputy took custody of him. This incident remains
under investigation.
The Grant County Sheriff’s Office would like to thank the Wisconsin State Patrol and Dane County
Sheriff’s Office for their assistance with this investigation.
Due to Jonah Riley being taken into custody, there is no threat to the public.