Three people were fatally shot and two wounded at the Greenwood Park Mall after a man carrying a rifle and several magazines of ammunition opened fire in the food court around 6:00 pm Eastern time.

Greenwood Police Department Chief Jim Ison told a news conference a 22-year-old from nearby Bartholomew County, who was legally carrying a firearm at the mall, shot and killed the gunman. The civilian's identity was not released.

"The real hero of the day is the citizen who was lawfully carrying a firearm in that food court and was able to stop the shooter almost as soon as he began," Ison said.

Ison called the incident "absolutely horrendous."

"This has shaken us to our core. This isn't something we've seen in Greenwood before. It is absolutely horrendous," the police chief said.

The identity of the gunman and a possible motive weren't immediately known. The shooter was described only as an adult male.

Police also confiscated a suspicious backpack that was in a bathroom near the food court.

"I'm not going (to) go into detail with the contents that were found in the backpack," Ison said. "That's still being processed. There was no explosive device, which was our primary concern in a situation like this."

The two people who were wounded included a 12-year-old girl, who suffered a minor injury to her back and was treated at a local hospital, according to WTHR-TV.

People inside the mall told the outlet they heard 20 gunshots in the food court.

A news conference with authorities is scheduled for Monday afternoon to provide updates.

Indianapolis Metropolitan Police and multiple other agencies are assisting in the investigation.

Greenwood is a south suburb of Indianapolis with a population of about 60,000. Mayor Mark Myers asked for "prayers for the victims and our first responders."

"As of now, we don't know the shooter's identity or motive," Myers said in a statement. "We do know that someone we are calling the 'Good Samaritan' was able to shoot the assailant and stop further bloodshed. This person saved lives tonight. On behalf of the City of Greenwood, I am grateful for his quick action and heroism in this situation."

Greenwood Park Mall said in a statement that it grieves for the victims and praised first responders as well as the "heroic actions" of the 22-year-old who police said fatally shot the gunman.

"Violence has no place in this or any other community," the mall said.

In a tweet, conservative radio host Todd Starnes commented on the shooting, noting: "This is why we have a Second Amendment." Subscribe for free to Breaking Christian News here

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