The victims of the US school shooting were shot multiple times by semiautomatic rifle, the medical examiner said on Saturday, and he called the injuries "devastating".

Police began releasing the identities of the 26 dead to a grieving community that had come to dread the coming Christmas holiday. All of the 20 children killed were 6 or 7 years old.

Donna Soto, the mother of teacher Victoria Soto, who was killed at Sandy Hook Elementary School, leans on her son Matthew at a candlelight vigil on Saturday in Stratford, Connecticut. A gunman massacred 20 children and six staff members at the school on Friday. Photo by Jared Wickerham / Agence France-Presse

"My daughter would be one of the first ones giving her support to the victims," said a tearful Robbie Parker, the father of victim Emilie Parker, age 6, as families started coming forward. "She was the kind of person who could just light up a room." He expressed sympathy for other families, including that of the shooter: "I can't imagine how hard this experience must be for you."

Police said they had found "very good evidence" they hoped would answer questions about the motives of the 20-year-old gunman, described as brilliant but remote, who forced his way into the school in one of the world's worst mass shootings. Witnesses said the gunman, Adam Lanza, didn't say a word and later killed himself. The Lanza family released a statement on Saturday night expressing "our heartfelt sorrow".

The medical examiner, Dr H. Wayne Carver, said he examined seven of the children killed, and two had been shot at close range. When asked how many bullets were fired, he said, "I'm lucky if I can tell you how many I found."

Townspeople took down Christmas decorations and sang Silent Night at memorials.

Stunned residents and officials continued on Saturday to fill in the details of the attack. Town education officials said the well-liked principal, Dawn Hochsprung, was killed while lunging at the gunman as she tried to overtake him.

In Newtown, a small and picturesque New England community about 95 kilometers northeast of New York City, nearly everyone seemed to know someone who died. Investigators said they believe Adam Lanza attended the school many years ago, but they had no explanation for why he went there on Friday.

Connecticut state police Lieutenant Paul Vance told reporters on Saturday that investigators had found "very good evidence" about the gunman, but another law enforcement official, speaking on condition of anonymity, said that investigators had found no note or manifesto of the sort they have come to expect after murderous rampages.

Just one person, a woman who worked at the school, was shot and survived - an unusually small number in a mass shooting - and Vance said her comments would be "instrumental". Authorities said Lanza had no criminal history; it was not clear whether he had a job.

Lanza was believed to have suffered from a personality disorder, said a law enforcement official who spoke on condition of anonymity. Lanza had attended Newtown High School, and several news clippings from recent years mention his name among the honor roll students.

On Friday morning, Lanza shot his mother, Nancy Lanza, at their home, drove to the school in her car and shot up two classrooms, law enforcement officials said, speaking on condition of anonymity.

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