Transcript for Clackamas Town Center Shooting: Who Is the Alleged Shooter?
Chilling, new details about the gunman who went on a shooting spree at an oregon mall this week. We are learning more about the shooter from his ex-girlfriend. Neal karlinsky is in portland, oregon, with the very latest on this. Neal, good morning. Reporter: Amy, good morning. That's right. We know a lot more about the shooter this morning. We know who he is. According to friends, he seemed to be troubled recently. But still, what no one understands is what set him off. This morning, as detectives continue to dig into his background, friends of accused shooter jacob roberts paint a portrait of a 22-year-old happy-go-lucky guy, who suddenly turned dark. I think something in his mind clicked. And it messed with his thinking. And he just wasn't himself anymore. Reporter: His friend says something seemed to have happened over the last few weeks. But no one knew what the problem was. And his ex-girlfriend, hannah sansburn tells abc news, he quit his job and sold all of his belongs, saying he was moving to hawaii. This is the last thing i expected. Especially from him. He was just too sweet. Never mean to anybody. Ever. Everybody loved him. Reporter: Police have no motive. But they also have no doubt. They say roberts carried out his shooting spree alone, with a stolen assault rifle. Among the dead, 54-year-old hospice nurse, cindy ann yuille, who was christmas shopping. This woman stayed with her and performed cpr. She died with dignity. And she did not die alone. Reporter:45-year-old steven forsyth was also killed. But 15-year-old kristina shevchenko was shot in the chest and survived. Amazingly, her second brush with death in a year, after being in a head-on car crash in august. It's clear to me, she's a very brave young woman. Reporter: That lucky young lady is in serious condition right now. She is expected to recover. Just remarkable this whole thing wasn't so much worse. Meanwhile, back here at the mall, shop owners are beginning to wonder when they can reopen, during this critical time of year for them.
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