Duane Morrison apologized for the actions he was about to take in a letter sent to his brother on the day of his fatal siege at Platte Canyon High School, authorities said Friday.
Even though it declares "this is not a suicide note," Park County Sheriff Fred Wegener said it referenced suicide many times.
The 14-page handwritten letter was delivered Thursday, having been postmarked Wednesday in Shawnee, immediately outside of Bailey.
The letter did not reference Platte Canyon High School or any other school, nor did it mention harming others, Wegener said.
"It doesn't tell me a lot of why, but it does maybe tell that the conclusion of the events of the 27th may have been my worst fears," said Wegener. "That he probably intended to kill both the young ladies and then kill himself or have us kill him."
Morrison took six female students hostage, sexually assaulted some of them, released four girls and then killed 16-year-old Emily Keyes as police broke in after a four-hour standoff Wednesday.
Also Friday, Emily's mother, Ellen Keyes, sent an e-mail to some participants of the recent PeaceJam event.
"Emily and I (and many others in our group) were at Peace Jam. We loved it. Emily loved it. You have sent such a powerful message. The only good thing that can possibly come from her death is to continue the message. We can't let the bad guys win," she wrote.
"Please continue with your strength. We want us and our children to be kind and strong. Practice random acts of kindness in the name of Emily."
PeaceJam co-founder Dawn Engle said she was touched by Keyes' effort to reach out.
"It's so strong and beautiful," she said.
Wegener said Morrison's letter, which appeared to have been written over several days, left him with the impression that Morrison had a calculated outcome.
"It was going to be either him or us," he said. "Unfortunately, Emily paid the price."
Colorado Bureau of Investigation Division Director Steve Johnson said he couldn't divulge everything in the letter until investigators had a chance to go over its contents with the families of those affected.
"I don't know at this point whether we'll be able to say what all he was trying to say in the letter. It takes a lot of different directions," he said.
CBI spokesman Lance Clem said Morrison sent the letter to one of his brothers. The brother presented it to authorities unopened, Wegener said.
Clem said he hadn't seen the letter but was told it is primarily directed to Morrison's family and doesn't shed much light on Wednesday's school standoff.
"It's long and doesn't seem to be all that clear about anything that happened," he said.
Investigators still chasing leads
In other news Friday, Wegener said:
Investigators are checking into a rumor that Morrison may have targeted his victims by trolling through the home pages for students at Platte Canyon on a social-networking website.
Detectives are still interviewing students, including one who says Morrison approached him with what he said was a list of female students. The identity of that student has not been released.
Two guns found at the scene were tied to Morrison, and preliminary indications link him to an assault rifle found down the road from the school. One of the handguns was traced to a relative, but authorities said there is not reason to believe the relative had any knowledge of his plans.
It appears that Morrison may have visited the high school in the days leading up to the attack, perhaps to conduct reconnaissance, the sheriff said.
And the high school, which has canceled classes and sporting events, will host a football game Tuesday at 3:30 p.m.
Violent threat in shooter's past
Clem said the CBI has completed its investigation of the school, though the criminal investigation of the hostage standoff and shootings continues.
Police records in Littleton show Morrison threatened two years ago to kill salesmen and staff at Rocky Mountain Harley-Davidson with an assault rifle.
During a profanity-laced Nov. 22, 2004, phone message to the Littleton store, Duane Roger Morrison complained about getting a promotional flier.
"What do you think it will take to get this stopped?" he asked. "Ah, maybe, ah, maybe a visit with an assault rifle? Damn, I'd sure hate for it to come to that. Maybe we can get something stopped before then."
"It's very disturbing," said Sgt. Sean Dugan, Littleton police spokesman.
Morrison was charged with harassment in the case. He was released on a $500 bond but failed to appear on the warrant. He was given a suspended sentence Aug. 15 of nine days in jail, according to court records.
The threat wasn't the first Morrison had given to staff at the motorcycle shop.
Linda More, 52, a Harley-Davidson employee, told police Morrison had previously made other harassing phone calls. He had also called company headquarters in Milwaukee to complain.
"I guess my last threat down there didn't carry very far. Ah, wow," Morrison said on his Nov. 22 phone threat. "Well, ah, what happened?"
Six months later, Morrison claimed that 15 pistols and rifles were among items stolen from his Denver apartment at 1300 S. Birch St.
Sometime in May, a thief had pried open his bedroom window and taken the items, including a .30-caliber Weatherby rifle and a .270-caliber Belgium rifle, both with scopes and each worth $2,000, Morrison reported.
Also stolen from his apartment was a watch, $310, a coin collection and binoculars.
