POSTED: Saturday, December 15, 2012 - 9:30pm
UPDATED: Saturday, December 15, 2012 - 9:34pm
NEWTOWN, Connecticut (CNN) — Authorities in Newtown, Connecticut, put together more pieces of the puzzle Saturday to explain exactly what happened inside Sandy Hook Elementary School, one day after a gunman opened fire there, killing 20 students and six adults.
All of the victims died from gunshot wounds and all were struck more than once, according to H. Wayne Carver II, chief medical examiner for the state of Connecticut. Their deaths have been classified as homicides.
"I've been at this for a third of a century. My sensibilities may not be the average man, but this probably is the worst I have seen or the worst that I know of any of my colleagues having seen," Carver told reporters.
He performed seven of the autopsies himself. Carver said the wounds he knew about were caused by a "long weapon." Asked by a reporter whether a rife was the primary weapon, he responded, 'Yes."
Of the children killed, all were either 6 or 7 years old -- 12 girls and eight boys. The adults ranged in ages from 27 to 56, and included the school's principal, psychologist and at least two teachers. State police released the victims' names and ages Saturday afternoon.
They were killed before the shooter apparently turned the gun on himself, ending the second-deadliest school shooting in U.S. history.
Searching for answers, major crime investigators from the Connecticut state police were combing "every crack and crevice" of the school.
They said they're finding some "very good evidence" there, and at the home of the man identified by authorities as the shooter -- 20-year-old Adam Lanza. Lanza's mother was killed at that house before the school rampage began, authorities said.
"The detectives will certainly analyze everything and put a complete picture together of the evidence that they did obtain, and we're hopeful -- we're hopeful -- that it will paint a complete picture as to how and why this entire unfortunate incidence occurred," said Lt. J. Paul Vance, a spokesman for the Connecticut State Police.
Vance said police are already talking to the one wounded adult at the school, a woman who has not been named.
"She has been treated and she'll be instrumental in this investigation, as I'm sure you can understand," he said.
Lanza was found dead next to three guns, a semi-automatic .223-caliber Bushmaster rifle and two pistols made by Glock and Sig Sauer, a law enforcement source told CNN. All belonged to his mother.
Nancy Lanza was a gun collector and recently showed off a newly bought rifle to fellow Newtown resident Dan Holmes, who owns a landscaping business in the town.
Adam Lanza also had access to at least three more guns, a second law enforcement source said. Investigators recovered a .45-caliber Henry Repeating Rifle, a .22-caliber Marlin Rifle and a .30-caliber Enfield Rifle, though it's unclear where they were found, the source said.
Among the dead are Dawn Hochsprung, the school's beloved principal, and school psychologist Mary Sherlach.
Based on CNN's contacts with friends and family members, CNN was able to identify two other adults killed at the school: Vicki Soto, a first-grade teacher, and substitute teacher Lauren Rousseau.
Vance said Saturday that Lanza forced his way into the school, though he wouldn't say how or whether Lanza used weapons to do it.
Authorities said it's also not clear whether Lanza entered before or after 9:30 a.m., the time each day when the school would lock its doors as part of a security system introduced this year. Authorities say the first emergency call about the shooting came in at "approximately" 9:30 a.m. Friday.
Within minutes, 26 people had been killed with chilling efficiency, leaving only the one wounded survivor, according to Vance.
"Stuff like this does not happen in Newtown," said Renee Burn, a teacher at another school in the town, which is roughly 60 miles northeast of New York City.
Until Friday, only one homicide in the past 10 years had been reported in the upscale community of expansive homes surrounded by woods, where many residents commute to jobs in Manhattan and the nearby Connecticut cities of Stamford and Hartford.
With the death toll at 26, the massacre in Newtown is the second-deadliest school shooting in U.S. history, behind the 2007 Virginia Tech mass shooting that left 32 dead.
Flags were lowered to half-staff in a number of states, and vigils were held at houses of worship and at schools amid a national outpouring of grief.
Two law enforcement sources said Adam Lanza lived with his mother. Contrary to early reports, they said, Nancy Lanza was not a teacher at Sandy Hook Elementary.
Investigators believe Lanza killed his mother and then took her guns and made his way to the elementary school wearing black fatigues and a military vest, according to a law enforcement official.
At about 9:30 a.m., as announcements were read over the loudspeaker to the nearly 700 students, the first shots rang out.
Students described being ushered into bathrooms and closets by teachers after hearing the first shots.
It sounded like "pops, gunshots," Janet Vollmer, a kindergarten teacher, said.
Vollmer locked her classroom doors, covered the windows and moved her 19 pupils toward the back of the room.
"We're going over in a safe area," she told the 5-year-olds. Then, she opened a book and started to read.
Outside Vollmer's classroom, a gunman was moving through the hallway of the one-story building.
In the first few minutes, the gunman is believed to have shot the principal, Hochsprung, and the school's psychologist, Sherlach.
One parent who was at the school in a meeting with Hochsprung, Sherlach and the vice principal said she heard a "pop, pop, pop." All three left the room and went into the hall to see what was happening. The parent ducked under the table and called 911.
"I cowered," she told CNN. The gunman "must have shot a hundred rounds."
Inside her classroom, Vollmer was still reading to the children when police officers banged on the locked door.
The kindergartners were told to line up and cover their eyes as they were led by police past bodies, presumably of their fellow schoolmates, Vollmer said.
As reports of the shooting made their way around town, frantic parents descended on a nearby firehouse where the children had been taken.
"Why? Why?" one woman wailed as she walked up a wooded roadway leading from the school.
People are sharing their concern and sadness over the Newtown school shooting. What are your thoughts? Share them with CNN iReport.
CNN's Susan Candiotti and David Ariosto reported from Newtown, Connecticut; Dana Ford from Atlanta. CNN's Chelsea J. Carter, Sarah Aarthun, Meredith Artley, John King, Ashleigh Banfield, Joe Johns, Terry Frieden and Michael Martinez contributed to this report.