A Multnomah County judge Thursday sentenced 16-year-old Blue Christian James Kalmbach to spend 11 years in custody for the torture of another teenager -- a crime she called "unthinkable in many ways.''

"It's hard to image how this crime occurred,'' Circuit Judge Jean Kerr Maurer said. "It's almost impossible to imagine this could happen between friends.''

Kalmbach, who turned 16 in June, is the last of four teens to be sentenced in the Feb. 10 attack and was the one identified by police as having struck Dustyn Murrain, then 16, in the head with a crowbar and carving a swastika into his forehead with a box cutter-type knife. He faced the longest sentence of the group.

Kalmbach pleaded guilty to three charges: first-degree kidnapping, first-degree robbery and second-degree assault.

"I just want to say that I'm very sincerely sorry,'' Kalmbach said in court, speaking softly and looking down as he stood before the judge. Kalmbach was 15 when the crime occurred, and was led into adult court in his juvenile detention garb, tan pants and a bright green T-shirt.

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His defense lawyer, Casey Kovacic, said" "No kid deserves to go through'' what Murrain endured. Kalmbach is genuinely sorry, but doesn't expect forgiveness, the lawyer said.

Kovacic described Kalmbach as a "deeply, deeply depressed kid'' and a teenager "who's never fit in, who's been bullied his entire life.''

"I hope at some point everyone will be able to move on from this point,'' Kovacic said.

When Kalmbach is released at age 27, "he's got a second shot at life,'' Kovacic said.

Statement from Brian Kalmbach and Amanda Britting

We would like to apologize to Dustyn, hopefully he can begin to put this behind him and move on.

While there is no excuse for what happened, Blue has been dealing with some mental health issues for much of his life and has been in and out of therapy for several years. He has not had a troubling home life and there has been no known cause of these issues. This incident is not indicative of the kind of person Blue is, he has always been a very caring and inclusive person who feels passionately about human rights and decency, and he has never been in trouble before. He did not have the tools necessary to deal with confrontational issues, and this is something he continues to work on. Hopefully he will be able to get the help he needs to become a mature adult who will someday become a contributing member of society.

Blue, your family knows you, and knows that you are a good person. The next several years are going to be challenging, but your family will always be here loving you and supporting you."

The teen's parents, Brian Kalmbach and Amanda Britting, had the defense lawyer read a letter to the judge on their behalf.

"While there's no excuse for what happened,'' his parents wrote, their son has struggled with mental health problems and has been in and out of therapy.

"He did not have the tools necessary to work on confrontational issues,'' they wrote.

Kalmbach's parents said they'd never known their son to be violent and told him they know he's a good person and is loved.

Dustyn Murrain, who celebrated his 17th birthday on Wednesday, sat in court with his mother, Kelli Murrain, and his girlfriend.

Kelli Murrain addressed the court. She called her son "resilient'' and said he's making progress.

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"Biggest question I have is how can anyone do this to another human being?'' she said. "It would be nice if someone can explain that to me.''

The teenagers had known each other from David Douglas High School, but none were attending at the time of the attack. Kalmbach previously told court authorities that Murrain had called him gay on Facebook and bullied him. Murrain's mother has said she suspects the horrific encounter stemmed from Kalmbach's anger that Dustyn Murrain was dating Kalmbach's ex-girlfriend.

Co-defendant 15-year-old Jenna Montgomery, police and prosecutors said, lured Murrain to the shed, where Kalmbach and two other boys confronted him. Police said Kalmbach struck Murrain in the head repeatedly with a crowbar and hit him with a revolver numerous times.

The defendants ordered Murrain to remove his shirt, then fired a BB gun at his chest, index finger and groin at close range. Kalmbach carved a swastika in Murrain's forehead while Jess Taylor, 17, held a BB air rifle trained on Murrain, police and prosecutors said.

When Murrain questioned what his attackers wanted, they demanded he return with a skateboard and money, an affidavit said. They rifled through his pockets and stole his iPod, according to court documents.

Montgomery and Taylor pleaded guilty last month to first-degree kidnapping, first-degree robbery and second-degree assault, and apologized to Murrain. Under plea deals, Montgomery was sentenced to nine years and 11 months in custody and Taylor to seven years and nine months.

Kalmbach, Montgomery and Taylor each will go to Hillcrest Youth Correctional Facility in Salem for intake. Kalmbach likely will spend the majority of his sentence in an Oregon Youth Authority-run facility, but could be transferred to adult prison at age 25.

The court also ordered the three defendants prosecuted in adult court to pay $3,470.85 in restitution to a family care agency. The three are splitting the cost, but none of their obligations are fulfilled until the full amount is paid. Kalmbach is to pay $297.95 to Dustyn Murrain.

Shane Connell, 14, was previously sentenced in Juvenile Court to 10 years. The shed where the attack occurred was on his grandparents' property.

After Thursday's hearing, Kelli Murrain said the scar on her son's forehead has faded so it's barely visible and he didn't require surgery. He wears long bangs to keep it out of view. He struggles with post-traumatic stress and nightmares, and is still angry, she said.

"He's holding up. He's happy that this is over,'' Kelli Murrain said. "All in all, he's a tough kid. He's a survivor.''

Dustyn Murrain plans to attend an alternative high school in the fall and pursue auto mechanic training, his mother said.

She said she hopes this case is a wake-up call to other youths who might step back and think about their actions before they do something stupid.

"These kids learned the hard way,'' she said. "I feel like we did get a little bit of justice for Dustyn. ... It's a fair sentence.''

--Maxine Bernstein