KNXV-TV(GOODYEAR, Ariz.) — An Arizona trooper who just graduated the academy in May was shot dead when a suspect stole a police officer’s gun during a struggle, authorities said.“The [Department of Public Safety] family is in mourning,” Colonel Frank Milstead of the Arizona Department of Public Safety said at a news conference. “Lives have been shattered and ruined.”The attack unfolded Wednesday night after authorities received calls about a driver swerving in and out of the lanes of Interstate 10, throwing items at cars, Milstead said.One trooper arrived, followed by two more troopers, including one who was finishing his field training, Milstead said.A fight broke out, during which two police officers from Goodyear, Arizona, arrived and helped try to take the suspect into custody, Milstead said.During the struggle, one of the trooper’s guns was taken by the suspect, Milstead said. The suspect then fired from the trooper’s weapon, hitting troopers Dalin Dorris and Tyler Edenhofer, he said.Dorris is in “good spirits, considering the circumstances,” Milstead said.But Edenhofer — who had just graduated from the state trooper academy in May — died from his injuries, Milstead said.“We’re all in a little bit of a state of shock this morning,” Milstead said. “Our thoughts and prayers are with his family.”It was not immediately clear which trooper’s gun was stolen.Edenhofer’s death came just hours after a 17-year veteran of the Milwaukee Police Department veteran was shot dead in the line of duty in Wisconsin.Gunfire was the leading cause of death among the 73 officers killed in the first half of this year, accounting for 42 percent of the deaths, according to the National Law Enforcement Officers Memorial Fund. Copyright © 2018, ABC Radio. All rights reserved.