BAILEY, Colo. -- "He said go to the front of the board and face the blackboard," a Platte Canyon High School teacher recalled.

With her voice trembling, the teacher, locked inside with a depressed gunman, said she didn't want to leave him with the students inside classroom No. 206.

But then Duane Morrison pointed a gun at her face and later fired a shot.

No one was hit but dispatchers ask the teacher where the round ended up.

"I don't know because he had just yelled at me when he fired, so I didn't see where he shot," she said.

The horror of the Platte Canyon High School shooting is made clear through the release of 911 dispatch calls.

They are part of a massive 5,000-page report displayed Monday for the media in Bailey, Colo.

Surveillance tapes from outside Platte Canyon High were also released, but they only catch a brief glimpse of Morrison as he enters the school just before 11 am on Sept. 27, 2006.

The teacher goes on to tell the Park County Sheriff's Department that Morrison was making dangerous threats.

"If anybody comes back in this room, I have explosives in this bag to blow up the school," she reports hearing Morrison tell her.

"We do have the school evacuated and we have the perpetrator isolated," an officer said on the tape.

The CBI's investigative report concludes that officers handled the Platte Canyon High School shooting the best way possible.

Park County Sheriff Fred Wegener held a news conference Tuesday afternoon to discuss the report.

The incident at Platte Canyon High School in Bailey six months ago left one student dead along with the gunman.

The report said Morrison, 53, was significantly depressed, had very few friends and had a mental state that was deteriorating rapidly.

"It seems that Morrison was set on the crime he was about to commit and there was going to be no changing his mind," Wegener said.

Morrison barricaded himself and seven girls in a room at the high school outside Bailey. He let four girls go before breaking off negotiations.

The FBI analyzed his suicide note, but investigators found no clear reason why Platte Canyon High School was targeted.

The report said that Morrison's attack was not based on revenge.

"There is no connection between Emily Keyes, the other hostages and Platte Canyon High School," Wegener said. "It turns out it was a random event."

The FBI concluded that Morrison told friends he felt emotionally and physically abused by his father and they believe that may be why he felt safe at school, and thus why he chose Platte Canyon High School.

Morrison molested or sexually assaulted the girls before killing Emily Keyes as SWAT officers stormed the room, using explosives to enter through the room's single door. One girl escaped, but Morrison fatally shot Keyes as she tried to run.

The report says that Morrison, who told officers he had three pounds of C-4 explosives in a backpack, did not have those items. However, the report states that he did have duct tape, handcuffs and sex toys in his possession, though the report concludes that those items were never used.

Morrison was hit by three shots fired by SWAT officers, but the report states he died of a self-inflicted gunshot wound to the head.

"I've made no bones about it," Wegener said. "Yes, I would have liked to have shot him, but I didn't get my chance."

Authorities have said school surveillance tapes showed Morrison's yellow Jeep in the parking lot of the school the day before as well as the day of the shooting.

Sections were released of the 14-page CBI summary, timeline of the events of the day, Morrison's letter, and the FBI analysis of Morrison's letter. The high school surveillance video and the audiotape of the 911 communications were also released.

The 5,000-page report, completed by the Colorado Bureau of Investigation, was presented to the Park County District Attorney's Office Monday, March 19.

"The report, while it's in law enforcement's hands, has a lot of information about the victims, the hostages in the case, that cannot be in the report when it's given to a non law-enforcement agency," District Attorney Molly Chilson told 7NEWS.

Staffers at the sheriff's department carefully removed names of all juveniles interviewed by various law enforcement groups in an effort to protect their identities.

"Three of our deputies on their off-time coach at this school, so this is very personal for them," said Park County attorney Steve Groome. "I hope this will bring some closure for them as well."

Groome said he believes the Bailey community will accept the findings in the report and may eventually become closer.

"It's like having a wound and it's finally starting to heal and scabbing over, and you bump that wound and it starts hurting all over again," Groome said. "It think that is part of what this community is experiencing."