WASHINGTON (Reuters) – A gunman killed three people when he opened fire in the food court of a shopping mall outside Indianapolis on Sunday before a bystander fatally shot the assailant, Greenwood Police Chief Jim Ison said. Two other people were injured in the incident, which took place in the early evening at Greenwood Park Mall, the Indianapolis Star reported. “The real hero of the day is the citizen that was lawfully carrying a firearm in that food court and was able to stop the shooter almost as soon as he began,” Ison told reporters. He described the armed bystander as a 22-year-old man….