(Hammond, IN) - An Indiana State Police trooper was shot in the chest and the gunman killed early this morning in Hammond.

Police said it happened after a vehicle was pulled over for a minor traffic violation on Interstate 94.  When back up officers arrived, police said the 34 year old driver from Gary pulled out a gun and opened fire.

The gunman, Aaron Barnes, was killed when officers returned fire.

Police said the wounded officer was taken to a Chicago hospital where he is expected to make a full recovery following surgery.

The name of the trooper was withheld but will be released at some point, according to police.