NEWTOWN, Conn. - Investigators on Saturday worked to understand what led a bright but painfully awkward 20-year-old to slaughter 26 children and adults at a Connecticut elementary school, while townspeople took down Christmas decorations and struggled with how to get through a holiday season that has suddenly become a time of mourning.
The tragedy brought forth soul-searching and grief around the globe. Families as far away as Puerto Rico began to plan funerals for victims who still had their baby teeth, world leaders extended condolences, and vigils were held around the U.S.
Amid the sorrow, stories of heroism emerged, including an account of Dawn Hochsprung, the well-liked Sandy Hook Elementary School principal, who lost her life lunging at the gunman, Adam Lanza, in an attempt to overpower him.
Police shed no light on the motive for the second-deadliest school shooting in U.S. history, though state police Lt. Paul Vance said investigators had found "very good evidence ... that our investigators will be able to use in painting the complete picture, the how and, more importantly, the why." He would not elaborate.
However, another law enforcement official, speaking on condition of anonymity, said investigators have found no note or manifesto of the sort they have come to expect after murderous rampages such as the Virginia Tech bloodbath in 2007 that left 33 people dead.
The mystery deepened as Newtown education officials said they had found no link between Lanza's mother and the school, contrary to news reports that said she was a teacher there. Investigators said they believe Adam Lanza attended Sandy Hook Elementary many years ago, but they had no explanation for why he went there on Friday.
Lanza shot and killed his mother, Nancy Lanza, at the home they shared, then drove to the school in her car with at least three of her guns, forced his way inside and opened fire in two classrooms, authorities said. Within minutes, he killed 20 children, six adults and himself.
On Saturday, Chief Medical Examiner Dr. H. Wayne Carver said all the victims at the school were killed up close with a rifle and were shot more than once. All six adults killed at the school were women. Of the 20 children, eight were boys and 12 were girls. All the children were 6 or 7 years old.
Channel 2’s Kerry Kavanaugh went to Newtown on Friday night, where hundreds of people packed St. Rose of Lima Church in a vigil for the victims. A stream of mourners lit candles, held hands and left notes for victims at the church.
"Hopefully, we can just open our arms and help people if they need it," Newtown resident Matt Svanda told Kavanaugh.
A crisis intervention team with Yale-New Haven hospital will be available for the community to help with the grieving process, and victim’s families have been assigned a trooper to help protect their privacy.
Vance said a school superintendent will address the public in the “not-too-distant future.”
Neighbors and others who knew Lanza’s family or had attended school with him describe a seemingly normal family -- but a somewhat distant child. Catherine Urso, who attended a Friday vigil in Newtown said her college-age son knew the killer and remembered him for his alternative style.
"He just said he was very thin, very remote and was one of the goths," Urso said.
Law enforcement officials said Lanza might have suffered from a personality disorder.
Another law enforcement official, speaking on condition of anonymity, said Lanza had been diagnosed with Asperger's, a mild form of autism often characterized by social awkwardness. People with the disorder are often highly intelligent. While they can become frustrated more easily, there is no evidence of a link between Asperger's and violent behavior, experts say.
The law enforcement officials insisted on anonymity because they were not authorized to discuss the unfolding investigation.
Acquaintances describe the former honor student as smart but odd and remote.
Olivia DeVivo, now a student at the University of Connecticut, recalled that Lanza always came to school toting a briefcase and wearing his shirt buttoned all the way up. "He was very different and very shy and didn't make an effort to interact with anybody" in his 10th-grade English class, she said.
Addressing the nation Saturday in his weekly radio and Internet address, President Barack Obama declared that "every parent in America has a heart heavy with hurt."
"Our hearts are broken today," Obama said. "We grieve for the families of those we lost. And we keep in our prayers the parents of those who survived, because as blessed as they are to have their children home, they know that their child's innocence has been torn away far too early."
Gunsmith: Shooter knew what he was doing
A Lawrenceville gunsmith said the Connecticut shooter had to know what he was doing with assault rifle.
"You consciously have to pull the trigger each time you want to shoot somebody," said Charles "Chuck" Calmbacher, owner of Doc's Gunsmithing Shop.
He told Channel 2's Shae Rozzi that he has 40 years of experience working with guns and holds a federal firearms license to work on
Calmbacher said that an AR15 is the civilian version of the military's M16 automatic rifle, the type of gun used in Friday's shooting.
He explained that one pull of the trigger on an automatic rifle fires off several rounds versus having to pull the trigger each time for each round.
Calmbacher said the guns are popular because of their military likeness and are most commonly used by recreational shooters.
"They're referred to as a modern sporting rifle used for hunting and target shooting, these are acceptable rifles for that purpose," Calmbacher said.
Different versions of the assault rifle can hold 5-10 rounds while some can hold up to 30 rounds.
"My heart goes out to them. There's no reason for this type of behavior," Calmbacher said.