On May 25, 2008 around 2:30 am in Winnemucca, NV, 30 year old Ernesto Villagomez entered a bar and executed two brothers, Jose Torres, 20, and Margarito Torres, 19. He then began shooting patrons in the bar, wounding a 22 year old woman and a 34 year old man, before another patron, a 48 year old man with a legally permitted concealed handgun, shot and killed Villagomez. He was initially taken into custody as a person of interest, but released when the district attorney determined that the shooting was a justifiable homicide.
While two people were killed and two were injured in the incident (three killed if you count the mass shooter), nobody was injured from the bullets shot by the man with the concealed handgun. In fact, had he not been there, it is very likely that many more people inside that bar would have been injured or killed.