Original Caption: Chicago — Braving bullets from a trapped safe-blowing gang, policeman Arthur Olsen trades shots with desperadoes as he seeks flimsy shelter behind a car. Olson injured his face when one of the gunmen fired through a plate glass of the currency exchange when he was the first to investigate the call. Olsen immediately called for re-enforcements for the battle, which lasted nearly an hour, in which two yeggs were slain, two captured, one believed to have escaped, and three policemen injured. (1947)

Great picture of a midcentury Chicago cop at work. (h/t Sam)