Updated

An off-duty police officer credited with helping stop a deadly shooting rampage at a Utah shopping mall said his experience helped him react quickly to confront the gunman.

Kenneth K. Hammond, who was at the mall for an early Valentine's Day dinner with his wife, said he first thought the sound of gunfire was construction noise but drew his gun and told his wife to call the police when he realized what was happening.

"I've been in situations before where I've had to chase a guy who was pointing a gun at me," Hammond, 33, said Tuesday.

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Investigators were still trying to figure out why Sulejmen Talovic, an 18-year-old Bosnian immigrant, opened fire Monday on shoppers, killing five and injuring four others.

Hammond, who fired on Talovic, is being credited with drawing the gunman's attention until other officers could reach the scene. Talovic was killed, although it was unclear which officer fired the fatal shot, police said.

"I feel like I was there and did what I had to do," Hammond said.

Talovic had a backpack full of ammunition, a shotgun and a .38-caliber pistol, police said. Investigators knew little about him, except that he lived in Salt Lake City with his mother, the police chief said. He was enrolled in numerous city schools before withdrawing in 2004, the school district said.

Talovic's aunt, Ajka Onerovic, emerged briefly from the family's house to say relatives had no idea why the young man attacked so many strangers. She said the family moved to Utah from Bosnia.

"He was a such a good boy. I don't know what happened," she told Salt Lake City television station KSL.

Talovic drove to the Trolley Square shopping center — a century-old former trolley barn with winding hallways, brick floors and wrought-iron balconies — and immediately killed two people, then a third as he came through a door, Burbank said. Five other people were then shot in a gift shop, he said.

Four people who were wounded remained hospitalized Tuesday, two in critical condition, two in serious.

One of the wounded shoppers, Shawn Munns, 34, was alone outside the mall after a meal with his wife and two stepchildren when Talovic blasted him with a shotgun, according to sister-in-law Jodie Sparrow.

With dozens of pellets embedded in his side, Munns staggered into a restaurant and warned diners about the gunman, Sparrow said.

Outside the mall, candles and flowers were left as memorials to those killed.

The state Senate wants to honor Hammond, said his boss, Police Chief Jon Greiner, who is also a state senator.

Hammond said Tuesday he didn't feel like a hero.

"We were there for a reason. I had my gun on me for a reason. We decided to eat dessert, which we never do, for a reason," Hammond said. "Everything happened for a reason."

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