(CNN) -- Friday began with the mundane. A chilly December day, Christmas on many residents' minds.
Newtown's center is magical this time of year with poinsettias, nutcrackers and twinkling holiday lights. Signs about town announce Christmas concerts and special events.
Just two days before, the students at Sandy Hook Elementary had enjoyed a rehearsal for the fourth-grade winter concert. How talented they were, said principal Dawn Hochsprung in a Twitter post accompanying a photo.
She'd shared other recent school photos: Of the book fairy and of kindergarteners paying the cashier in teacher Janet Vollmer's Supermarket Center, which she used in the school as a teaching tool.
Vollmer loved teaching -- she'd been doing it for 20 years. She said what made her laugh were the things the children would say. Sometimes, it was just the way they interpreted things, she told the local newspaper.
Friday morning, Vollmer made her way to the school she's called home for 15 years.
About 50 other teachers and staff and 700 young students were doing the same. Among them, Hochsprung, teacher Victoria Soto and the children of Robbie and Alissa Parker, Robert and Diane Licata and Laura and Nick Phelps.
They lived in an idyllic New England town straight out of a Robert Frost poem. People knew one another. They were firm in their faith and community. It all seemed unshakable.
Normalcy unravels with alert
Diana Licata was supposed to go to the school later to help build a gingerbread house in her son Aiden's class. She told her husband, who was working from home Friday, that maybe he should go instead. Aiden would love to have Daddy come to class.
Robert planned to be in Victoria Soto's classroom at 2 in the afternoon.
Nick and Laura Phelps made plans for a date in New York. It would be a fun Friday night without the kids.
In another Newtown house, 6-year-old Emilie Parker woke up to say goodbye to her father, Robbie, before he left for work at a local hospital.
He had been teaching Portuguese to his daughter, and she practiced by saying "bom dia" (good morning) and asking how he was.
Emilie told her daddy she loved him and gave him a kiss. Then Robbie Parker dashed out the door.
But the normalcy of the day began to unravel after Sandy Hook parents received an electronic alert shortly after classes began at 9:30.
It announced that all Newtown schools were in lockdown because of a reported shooting.
A quiet kid
Former classmate Alex Israel described him as a pretty clever young man. He was especially good in math. He was reserved and quiet, said Israel, who'd known Lanza since first grade. She thought of him as someone who flew under the radar, not someone who would ever do anything crazy.
He'd moved to Connecticut in 1998 from Kingston, New Hampshire, with his parents, Nancy and Peter, and brother Ryan. He enjoyed soccer, skateboarding and video games, according to a neighborhood booklet.
Marsha Moskowitz remembers driving the school bus Lanza rode for three years when he was a teenager. He'd sit in the back, usually alone.
He was quiet and shy. He was one of the older kids on the bus and probably was embarrassed by it, she thought.
When Lanza was 17, his parents divorced. Peter Lanza remarried and lived not far from Newtown. Adam lived with his mother.
One of his aunts described him as a "challenge." She said Nancy Lanza "battled" with the school board and ended up having her son home-schooled.
Nancy was a gun collector and showed off a rifle she'd recently purchased to Newtown resident Dan Holmes.
She told Holmes she'd go target shooting with her boys pretty often.
On Friday, Lanza took one of his mother's guns and killed her at their house.
He put on black fatigues and a military vest. He grabbed three guns from the house -- a semi-automatic AR-15 assault rifle made by Bushmaster and pistols made by Glock and Sig Saeur -- and made his way to the school.
'Pop, pop, pop'
Everyone at Sandy Hook felt safe in the school building on Dickinson Drive.
Earlier this year, Hochsprung had a new security system installed. It required all the school doors to be locked by 9:30 and visitors to be visibly identified before being buzzed in.
School started Friday with announcements on the PA system. Hochsprung was in a meeting with the vice principal, and the school's psychologist, Mary Sherlach, was in a room near the entrance.
The mother of a struggling second grader had come in to discuss her child. That's when Lanza blasted his way inside.
The mother in the meeting heard a "pop, pop, pop." The sound was coming from the hall. She ducked under the table. She cowered.
She must have heard at least 100 rounds, she said. "Just shooting and shooting and shooting."
She dialed 911.
Hochsprung, Sherlach and the vice principal stepped out to see what was going on. The vice principal was wounded in the foot. She was the only one of the three who came back into the room.
The school's PA system was still on from the morning announcements and every sound in the building was amplified.
Every pop, every bang, every boom was that much louder and clearer.
When she heard the crackling over the PA, school library clerk Mary Ann Jacob called the office to tell them the system was still on. The office staffer told her there was a shooter in the building.
She had practiced lockdown drills many times with the kids. They knew they were supposed to go a spot between bookcases against a wall. They couldn't be seen from the windows there.
But then Jacob realized one of the doors in the room wasn't locked. So she hustled the 6-year-olds under her watch into a back storage room and locked them in there. She handed out pieces of paper and crayons to keep them quiet.
When Lanza began shooting, some of the students thought the noise was the clanging of pots and pans. One teacher thought it was folding chairs brought in for a concert falling to the ground like dominoes.
Fourth-grader Brendan Murray was inside the school's gym. He thought the custodian was knocking things down.
First-grader Aiden Licata, whose class was going to make the gingerbread house, thought it was the sound of hammers.
Aiden's teacher, Victoria Soto, and other school employees scrambled to get the students into safe areas of the building.
Janet Vollmer closed her classroom doors, locked and covered the windows and began reading a story to her kindergarteners to keep them calm. But they all knew something was terribly wrong.
"We're going to be safe," Vollmer told them, "because we're sitting over here and we're all together."
First-grade teacher Kaitlin Roig heard what sounded like the rapid firing of an assault rifle.
She herded her students into a bathroom. She helped some climb onto a toilet so they could all fit in the tiny room. Then she locked the door.
"I just told them we have to be absolutely quiet," she said.
As the minutes ticked by, the children asked Roig if she could "go see if anyone is out there."
No, she told them.
"If they started crying, I would take their face and tell them, 'It's going to be OK.' I wanted that to be the last thing they heard, not the gunfire in the hall."
Abbey Clements tried to keep calm for the sake of her students, she said. But she couldn't hide her fear.
"Mrs. Clements," they said. "You are shaking."
She wanted quiet so she could hear any instructions that might come over the loudspeaker system. But she also wanted to shout to drown out the constant sounds of gunfire, to shield little ears.
In a nearby classroom, Alexis Wasik, 8, began putting it all together when she heard the sirens outside. There had been a shooting at the school. Alexis and her classmates huddled together in the back of their classroom. Children were crying. Some were screaming.
Not everyone could see what was happening. But they could hear.
Chaos. Pandemonium. Horror.
After Lanza forced his way into the school, he shot Hochsprung and Sherlach when they stepped into the hallway.
Then he unleashed a hail of bullets inside two classrooms. In one was Lauren Rousseau, a substitute teacher who was filling in for a teacher out on maternity leave.
Lanza systematically shot everyone inside.
"There were 14 coats hanging there and 14 bodies. He killed them all," a law enforcement officer told the Hartford Courant.
The other classroom Lanza entered was Soto's. Her students were huddled behind her when Lanza burst in. He didn't say a word. He just pointed his rifle and sprayed the room with bullets.
A place that had been sanctuary was turned into hell.
For some, relief
Within 20 minutes, an army of police and emergency responders descended on Sandy Hook Elementary.
Lanza was in Soto's classroom when he heard the police closing in, officials believe. He shot himself with one of his hand guns.
Police marched the surviving students out of the school according to protocol for evacuating children. They asked them to put their hands on the shoulders of the kid in front of them, connected to each other like the cars of a train. They were told to close their eyes and walk out single file to a nearby firehouse.
Some stumbled past bullets and bodies. Then they ran to the firehouse. In tears. In shock.
By then, word of the shooting had spread. Parents rushed to the school, scrambled frantically to find their children.
"It was terrifying," said Brendan's father, Sean Murray.
"You're rushing over here, and you can't get to where you need to go," he said, relieved to know his son was safe.
John Voket, one of two associate editors of the Newtown Bee, arrived on the scene at about 10:15 a.m. Everything seemed surreal, time seemed to have halted.
His colleague, Shannon Hicks, is also a volunteer firefighter and received a dispatch from the fire department to respond to the shooting. She was one of the first people on the scene.
One of her photos captured what may have been the first students evacuating the school, the panic evident on their faces.
Voket knew many of the parents. He also knew many of the emergency responders. This was turning into a horrific story to cover.
Local officials had sent a massive number of responders, thinking there would be dozens of people to take to hospitals. Two victims were evacuated for medical care, but soon it became clear that there would be no one else.
Laura Phelps found her kids and held them tight.
Diana Licata arrived at the school and drove over the curb into the firehouse parking lot.
She eyed the children coming out class by class. Where was Kaelyn? Aiden? She couldn't see her children.
She felt she was living Columbine. All those images that had once been relegated to television, that had once been someone else's fears, suddenly were her reality.
She spotted Kaelyn's teacher. "Where is she?" The teacher didn't know.
Then, Licata saw Kaelyn coming out of the school. She grabbed her and told her to go wait inside the fire station. Licata waited for Aiden. But there were no more children coming out of the school. Her heart pounded. She felt a kind of helplessness she could not describe in words.
Where was Aiden? He has to be safe.
Relief came in the form of a text on her phone. Aiden, she learned, was in the firehouse already.
He had come face-to-face with the gunman when he entered Soto's classroom and ran right by him to escape, he later told his parents.
Licata felt guilty in her relief. She knew there were parents whose insides were about to be ripped to shreds.
The families of missing children walked up a rolling hill and past a cemetery to get from the school to the nearby brick firehouse.
This is where the people of Newtown came for lobster bakes and dances to raise money for the volunteer fire department. They knew it as a place of joy -- until Friday.
Parents' lips quivered; their eyes reddened with tears. The firefighters who escorted them seemed almost as shaken.
In the back of the firehouse, there's a common room and a kitchen. A big-screen TV was showing cartoons for the children who were there Friday. Many were siblings of the children who hadn't come out of the school.
The sounds of the cartoons seemed enormously incongruent to what was happening inside, thought John Woodall, a psychiatrist and member of Newtown's interfaith council, who arrived in the early afternoon to help console people.
The firehouse, he said, had become a place to hold people -- physically and emotionally.
Restaurants donated food. Pizza and a full buffet of food were kept warm with Sterno burners. But no one was eating.
Parents were still trying to figure out what had happened. If their child was missing, did it mean he or she was sent to hospital? Did they run out into the nearby woods? The more time that went by with no news, the more desperate they became.
During a service at the firehouse, Woodall wandered around. He wanted to find people who might be by themselves, people who perhaps didn't know how to receive care. He saw a woman standing apart from the rest of her family. She looked so fragile to him that a whiff of wind might have shattered her.
He said nothing. He hugged her. She hugged him back.
"I don't know where my grandson is," she said. "What have they told you?" Woodall asked.
She said there was a list. A list of the dead.
The problem was that officials wanted to make absolutely certain of the names on that list before they released it. That's why it was taking so long.
Connecticut Gov. Dan Malloy was finally given the list at about 3 p.m., Woodall said.
On it were 26 names; 20 were children.
Charlotte Bacon, 6; Daniel Barden, 7; Olivia Engel, 6; Josephine Gay, 7; Ana Marquez-Greene, 6; Dylan Hockley, 6; Madeleine Hsu, 6; Catherine Hubbard, 6; Chase Kowalski, 7; Jesse Lewis, 6; James Mattioli, 6; Grace McDonnell, 7; Emilie Parker, 6; Jack Pinto, 6; Noah Pozner, 6; Caroline Previdi, 6; Jessica Rekos, 6; Avielle Richman, 6; Benjamin Wheeler, 6; Allison Wyatt, 6.
Eighteen of them never made it out of the building; two died in hospital.
Six school employees, all women, were also dead.
Among them: Hochsprung, 47; Sherlach, 56; Rousseau, 30; and Soto, 27. Two other employees -- Rachel Davino, 29, and Anne Marie Murphy, 52 -- were also killed.
All 26 were struck by bullets several times, H. Wayne Carver, the state medical examiner, later told reporters. Carver had been in the business of inspecting bodies for more than three decades. This was the worst he'd seen.
Those who were standing outside the firehouse heard the wails and moans as mothers and fathers learned they would never see their children again.
Robbie Parker learned his daughter, Emilie, was gone forever. He would never see her smile again. Her two younger sisters would never be able to count on Emilie again for comfort.
"Why? Why?" one woman cried as she walked away.
Woodall stepped outside to find the grandmother he had hugged earlier. He told her the devastating news: Her grandson's name was on the list.
Some people fled the firehouse. Others lingered for a while. Their world was broken. It would never be whole again, not like it was.
Coping through faith and love
A gunman changed Newtown within a matter of minutes. By the afternoon, it changed again as hundreds of journalists descended on the small town.
Church Hill Road was lined with satellite trucks. One resident said the Starbucks was teeming with reporters who needed Internet access.
Mixed in with all the Christmas signs now were ones that said: "No press beyond this point" or "Church is open."
Flags flew at half-staff. People across the nation gathered for candlelight vigils in tribute to the victims. President Barack Obama wiped away tears as he spoke in Washington about the terrible loss.
In Newtown, residents spilled out of the St. Rose of Lima Roman Catholic Church for a vigil. There wasn't enough room to accommodate everyone. They shed tears, clutched one another and tried to comprehend the tragedy.
Those who were reunited with their children clung to them as though they would never let go again.
They clung to their faith as they grappled with how their children would cope. How could they trust again after seeing such tragedy?
Many children did not know yet that their friends were dead.
Parent Lisa Terifay captured the anxiety and grief of the Sandy Hook community on her Facebook page.
"In a few hours the more difficult part of this whole thing will begin," she wrote.
"We'll start hearing stories of the people who didn't make it safely out of our beloved Sandy Hook Elementary. The kids will find out that their amazing principal was killed. ... I mourn the loss of a beautiful 7-year-old-boy, Chase Kowalski. To imagine his sweet face and his life ending that way is more than I can put into words."
Aiden Licata knew his beloved teacher had been hurt, but he didn't know Soto was never coming back.
"He's reassuring himself that she is going to be OK," Diana Licata said. "He keeps saying, 'I really hope it's not her.' "
The Licatas tried their best to console their children.
As did Nick and Laura Phelps. They hadn't said much about the shooting to their son, a first-grader, and daughter, a third-grader.
They knew their 6-year-old was unaware he had lost close friends. They knew both of their children had heard bad things. They wanted to make sure that they, as parents, said the right words.
"We're going to learn what to say before we say it," Laura Phelps said. "We're going to live in our church." And seek counseling.
For the time being, they stuck close to their kids. Friday night, the whole family -- including their two middle-schoolers -- crawled into one bed.
Christmas filled with loss
Robbie and Alissa Parker spent Friday night knowing their daughter's body was still inside the school. Authorities had to make sure they identified every person before they could release the bodies.
It would be many hours before America would know of the Parkers' grief. Police released "the list" to the media Saturday afternoon.
Robbie Parker stepped forward to tell the world about his little Emilie. Of her smile and her compassion and how she carried around her markers and pencils so she'd never miss an opportunity to draw a picture or make a card for those around her.
"As the deep pain begins to settle into our hearts, we find comfort reflecting on the incredible person that Emilie was and how many lives that she was able to touch in her short time here on Earth," he said.
"She loved to use her talents to touch the lives of everyone that she came in contact with."
Parker offered his condolences to all the families affected. That included the family of the shooter.
"I can't imagine how hard this experience must be for you, and I want you to know that our family, and our love and support goes out to you as well."
America watched as a father wept openly over the loss of his bright light, as he struggled to compose himself.
The reach of his words was long -- in Newtown, reeling from shock, and in the rest of the nation, trying to comprehend another stain on its history.
Tragedy has a way of stripping people of artifice and exposing the very best of people. There is often a beauty in human frailty in its purest.
Robbie Parker is an example of that, as are many of the residents of Newtown. With their lives shattered, they searched for ways to cope. Not just on Friday and this horrible weekend, but they'll do so in the many days to come.
Signs in town asked for prayers, love and hope.
Just a few days before Christmas, Newtown's usual holiday glitter was now punctuated with sorrow. People hung ornaments on a Christmas tree near a memorial at Sandy Hook Elementary. One resident suggested the town hold a Christmas Day vigil.
And a holiday wreath in the center of town bore the names of the dead. Strangers inspired to honor Newtown victims
CNN's David Ariosto, Rose Arce, Meredith Artley and Chelsea Carter contributed to this report. Additional material was used from ABC News and KPCC Radio.