Who was Jacob Tyler Roberts?

CLACKAMAS, Ore. - While we may never know exactly why a young man opened fire at the Clackamas Town Center in a deadly rampage, details about his life are emerging.

The mall shooting on Tuesday left three people dead, including the gunman, and a teenage girl badly injured. The suspect, 22-year-old Jacob Tyler Roberts, turned the gun on himself, police said.

Jacob Tyler Roberts now joins the list of others whose names and faces are forever linked to tragic killing sprees, like Eric Harris and Dylan Klebold or Kip Kinkel.

What led Roberts to this point is a mystery, according to those who knew him. His aunt, Tami Roberts, is at a loss to explain why this happened, according to a family friend who spoke on her behalf. Tami Roberts is an aunt who raised Jacob and she is referred to as his 'mom' by the family.

"Tami has no understanding or explanation for her son's behavior," the family spokesperson said. "We're very sorry for everyone's loss. He's always been a good boy."

The family friend said Roberts was a popular boy and everyone applauded when he got his high school diploma. She said the entire family is confused because Roberts "doesn't fit the profile."

• Aunt of mall shooter writes note saying 'sorry'

Hannah Sansburn dated Roberts and said he planned to move to Hawaii. He quit his job and sold everything he owned, already had his plane tickets and was on his way to start a new life last Saturday.

"He said there was nothing left for him here that would tie him down," Sansburn said.

Roberts obviously never left and friends said they never actually saw the airline tickets.

"I hate him for what he did, but I can't hate the person who I knew," Sansburn said. "That's what's so mind-boggling, because that was not the person I knew. The person I knew never, ever would do anything like this."

Leah Reed, a friend of Roberts, was just as stunned.

"He never showed signs of this," Reed said. "What he did was wrong and I understand that. And I know those two families are mourning their loss. But on the other hand we are mourning ours too."

An acquaintance of Roberts (who just wanted to go by her first name, Brittany), said she remembers the young man as jovial, popular and nice to classmates at Milwaukie High School. She said he loved skateboarding.

She saw no indicators of any problems in high school, nor in seeing recent updates of him on Facebook.

“I am as astonished as anybody. I would have never, ever, ever thought this would happen,” she said. “As far as I knew, he was happy.”

She said Roberts was never a loner and never showed any signs of violence. She said she had a couple classes with him toward the beginning and middle of high school, but lost track of him by senior year.

"He was a popular guy. Lots of people liked him, loved him. He was really nice,” she said. “He had so many friends."

A Facebook photo shows Roberts taking target practice at an outdoor range. His friends said they thought target practice was all that it was. There was never a word spoken of even pointing a gun at another person.

Johanna Petrie also once dated Roberts and had a different perspective.

"I really think he was lost in a lot of ways," she said. "He needed to find himself before he could help himself."

"It's just weird," said Ken Hargove, who partied with Roberts. "Four days ago we were hanging out with the guy. We had a drink with him, were laughing and having fun, you know, and then all of a sudden we heard this happened."

A neighbor near his house said Roberts was renting out the basement of a home in the 7300 block of Southeast 84th Avenue, just off Southeast Flavel.

Hau Nguyen lives right next door to the suspect's home and said he was shocked to learn that his neighbor is the man suspected of opening fire at the mall. He said he had seen the man a few times and given a few courteous hellos, but didn't know much else about him.

Police officers stand outside the home of the mall shooting suspect on Wednesday, Dec. 12, 2012. Photo by Shannon L. Cheesman, KATU.com Producer/Reporter.

Amber Acrey lives nearby and said she had brought mail to the house a couple of times, most recently about a week ago. Her address is the same as the suspect's address, but one street over so the mail had gotten to the wrong place.

"We just talked to him at the door," she said. "Told him 'we've got your mail, here you go.' He seemed like a nice gentleman. There didn't seem to be anything strange about him."

"He seemed normal," she added. "He seemed like an everyday person. He didn't seem like he was in distress. It didn't seem like anything was bothering him. I'm a drug and alcohol counselor so I can tell when something is bothering somebody. He didn't seem anything like that at all."

Acrey said there was nothing unusual about the mail - just your average stuff like bills.

KATU Reporter Dan Tilkin talks to resident Amber Acrey on Wednesday, Dec. 12, 2012. Acrey said she met the suspect twice, most recently in the last week, to deliver mail that had been inadvertently dropped off at her home. Photo by Shannon L. Cheesman, KATU.com Producer/Reporter.