A statement on the Athens, Ga.-based group's website says Tom Torrisi fell ill Thursday morning as the charter bus was traveling on Interstate 35 south of Ames. The bus went off the highway, and the band's merchandise manager took the wheel.
The band says one crew member suffered a head injury when the bus went off I-35.
Widespread Panic performed Thursday night in Ames as scheduled.
Jessica Lown of the Iowa Department of Criminal Investigation told the Ames Tribune that she couldn't confirm details of the bus incident.
A 10-mile stretch of I-35 was closed Thursday morning after the bus incident and two subsequent crashes.