GREENWOOD, Ind. (NewsNation) — Authorities say the person who shot and killed three people at a Greenwood mall before a civilian shot and killed him was a 20-year-old local man.

Jonathan Sapirman, of Greenwood, began firing after leaving a bathroom at the Greenwood Park Mall shortly before it closed Sunday evening, Greenwood police Chief James Ison said at a news conference.

Sapirman continued shooting people until he was shot and killed by 22-year-old Elisjsha Dicken, of nearby Seymour, who was shopping with his girlfriend, said Ison.

“Many more people would have died last night if not for a responsible, armed citizen,” said Ison, noting that authorities were still trying to determine a motive for the attack.

The deceased have been identified as Pedro Pineda, 56, of Indianapolis and his wife Rosa Mirian Rivera de Pineda, 37. Victor Gomez, 30, of Indianapolis, has also been confirmed as one of the victims.

Two other people were injured in the shooting, including a 12-year-old girl. Both of them are in stable condition.

Ison said after Sapirman entered the mall, he walked into a bathroom where he spent about an hour before he emerged and opened fire. Ison said investigators believe Sapirman spent that time preparing and possibly assembling a disassembled rifle that he had brought in his backpack. He ended up firing 24 rounds within two minutes.

Although authorities said Dicken was legally armed, the mall prohibits people from carrying weapons on its property.

As of July 1, Indiana law allows anyone age 18 or older to carry a handgun in public except for those prohibited for reasons such as having a felony conviction, facing a restraining order or having a dangerous mental illness as determined by a court. Indiana’s Republican-dominated Legislature retained provisions in the law that allow private property owners to prohibit firearms.

This mass shooting was just the latest to unnerve Americans in 2022. Schools, churches, grocery stores and a July Fourth parade in Highland Park, Illinois, have all become killing grounds in recent months. Still, the reality of America’s steep murder rate can often be seen more clearly in individual deaths that rarely make the news.

The Associated Press and WXIN contributed to this report.