Investigators are searching for a motive following Tuesday's deadly mall shooting in the Portland, Oregon suburb of Happy Valley.
Police say 22-year-old Jacob Tyler Roberts entered the mall carrying an assault rifle and opened fire on surprised victims.
Panicked shoppers rushed out as officers moved in.
Ushered to safety, witnesses described the chaos inside, as the shots rang out.
"People jumping, babies crying, it was unreal," said one survivor.
An army of first responders swarmed the crowded mall.
"We had people at the mall within minutes and teams were deployed responding quickly to basically hunt down, find this guy in the mall," said Clackamas County Sheriff Craig Roberts.
Witnesses say Roberts was dressed in camouflage and body armor and wore some kind of mask as he walked through the mall firing.
"It was very apparent that he had a mission set forth to take the lives of people in that mall," added Sheriff Roberts.
Two people, 54-year-old Cindy Ann Yuille and 45-year-old Steven Mathew Forsyth were killed and a third person was injured before the gunman took his own life.
Family members say the 15-year-old wounded in the wave of bullets is in stable condition at an area hospital.
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