The lone suspect in a shooting at a mall in Boise, Idaho, on Monday that killed two people died on Tuesday of injuries he received in an exchange of gunfire with the police, according to the police.
The authorities were still investigating the motive for the shooting, in which they say the suspect, Jacob Bergquist, 27, of Boise, fatally shot a security guard, Jo Acker, 26, of Caldwell, and Roberto Padilla Arguelles, 49, of Rupert, at Boise Towne Square.
At a news conference on Tuesday, Chief Ryan Lee of the Boise Police Department said that Mr. Bergquist had frequented the mall and was known to mall security for calls categorized as disorderly conduct, trespassing and disruptive behavior.
Chief Ryan said that investigators were still interviewing people who knew Mr. Bergquist and examining social media to try to understand what had led to the attack.
“We’re still very early on in that investigation,” he said, “and there’s not much information that I can share relative to that.”
Four people were injured in the shooting, including a 23-year-old woman and a 52-year-old woman who were injured inside the mall, and a 68-year-old woman who was shot in her vehicle outside the mall, according to the Boise police. All three women had non-life-threatening injuries, they said.
The fourth person injured by gunfire was a police officer who was treated at a hospital and released on Monday.
Officers responded to reports of shots fired at the mall about 1:50 p.m. on Monday, the police said. Callers told dispatchers that an armed man had fired several shots inside the mall, according to the police.
A security guard on the first level of the two-story mall initially “contacted” the suspect near a department store on the west side of the mall. The gunman shot and killed the guard.
The police said Mr. Bergquist then fired several rounds inside the mall, including shots that struck a glass elevator and a second person, who later died at a hospital. The gunman continued firing, injuring four other people, they said.
When the police arrived at Boise Towne Square, they saw the gunman running out of the mall. The gunman and the police exchanged gunfire. An officer was shot through the window of his vehicle, the police said.
The police said 18 used shell casings were found inside the mall, and that they had executed a search warrant on Tuesday at a home in Boise as part of the investigation.
A man who was fleeing the mall after the attack was injured when he fell, the police said, and was treated at a hospital. The chief said it was possible the number of injuries would rise as the investigation continued, given the number of people who “self-evacuated, running for their lives.”