One man is dead and an Illinois State Trooper was seriously wounded in an exchange of gunfire that happened during what was expected to be a routine traffic assist.

On Tuesday at around 3am on Interstate 64 near Mt. Vernon a trooper stopped to help 23 year old Brandon Griffin from Alburquerque NM and his female passenger.

Something caused an altercation between Griffin and two troopers on the scene and the shooting occured.

The wounded trooper is a 16 year veteran of ISP and he is being treated at a Jefferson County hospital

Special Agents of the Illinois State Police Division of Internal Investigation are investigating the incident.