A map in the Ada County sheriff's office shows the path of a violent 6,500-mile road trip across the West marked in a jagged erratic line.

The personality of the man suspected of shooting three people along that path, including two former high school classmates, has been described in much the same way.

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Investigators were trying to determine whether an event during high school might have triggered the attacks years later, and police said others involved in an "incident" during his sophomore year at Timberland High School may have been at risk before his arrest.

But Latah County prosecutors said there was no particular incident, and Moscow police declined to release any additional details.

At Timberland High School — the city's newest high school, nestled in suburban southern Boise with just over 1,000 students — teachers declined to comment and a district spokesman did not return phone calls Wednesday.

"He wasn't so much an outcast as he just wasn't really in with the in crowd," in school, Ada County Lt. Scott Johnson said. "We just don't know if he had any close friends. By some accounts, the two people he shot were the nicest to him."

Delling is charged with the first-degree murder of University of Idaho student David Boss on March 31. Police also suspect him in the slaying of Meridian resident Bradley Morse in Boise a few days later, and the March 20 shooting of University of Arizona student Jacob Thompson. Thompson survived the attack outside his Tucson, Ariz., home.

Delling, Boss and Thompson attended high school together. Morse went to school in nearby Meridian at about the same time.

While not popular, he ran with a circle of five friends, his mother once testified.

"We're just confused why this would happen," said Christina Navarro, a friend of Boss' and a former classmate of Delling. "We knew he was trying to be there for John Delling in the past — he just really wanted to help him, when everyone else just wanted to stay away from John."

Family members and court documents suggest that a struggle with mental illness may have marred Delling's life — so much that family members took his guns away and sold them, according to police reports.

"John was very sick, and that's all I can tell you," Delling's mother, Carol Delling, said recently.

During a visit at their his home in Antelope, Calif., police reports say, John Delling allegedly asked his brother, "Do you think David (Boss) is the one stealing my powers?"

John Delling had made similar claims before, the report said, but this time he apparently became so agitated that he began damaging his parent's bathroom. Local law enforcement had to be called to ask him to leave, police said.

While in high school, he pleaded guilty to battery in juvenile court after beating a classmate with the anti-car theft device "the club." Witnesses said Delling, then 17, claimed he wanted to kill the student for ruining his life.

A short time later, he transferred from Timberline to Boise High School.

At 19, Delling was convicted of misdemeanor battery for trying to run down a 13-year-old boy with his motorcycle, Johnson said. The boy suffered only scratches, police said.

In 2005, Delling was cited for misdemeanor disturbing the peace in Moscow, Idaho, and was kicked out of the University of Idaho after being accused of threatening residents in dorms, assistant police chief David Duke said.

That summer he pleaded guilty to stalking three men in Boise and was ordered to have no contact with them.

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