( CNN ) -- A Pennsylvania wildlife officer investigating possible poaching was killed during an exchange of gunfire after making a traffic stop late Thursday , authorities said . David L. Grove , 31 , was fatally shot in Freedom Township near Gettysburg , according to State Police Commissioner Col. Frank Pawlowski . Authorities detained Christopher Lynn Johnson , 27 , early Friday , and were in the processing of bringing charges against him in the case , according to Adams County District Attorney Shawn Wagner . Johnson sustained a gunshot wound and was receiving treatment at a nearby hospital , Pawlowski said . `` It is truly a painful day for the Pennsylvania Game Commission , '' said department spokesman Jerry Feaser . Grove was a `` bright , highly educated conservation officer '' who graduated from Pennsylvania State University with a degree in wildlife and fisheries science , he said . Grove is the first the game commission officer to be killed in the line of duty since 1915 , and only the third since the game commission was founded in 1895 .
Pennsylvania game commission fatally shot . Suspect sustained gunshot wound and is in police custody . David Grove is the first game commission employee killed in the line of duty since Reconstruction .