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Connecticut school shooting: 'Screams were coming over the intercom'

The shootings at Sandy Hook Elementary School left the quiet community of Newtown, Conn., desperately trying to understand what happened. NBC's Kate Snow reports.

Updated at 7:17 p.m. ET: The first that some pupils heard of the mass shootings Friday at their Connecticut elementary school was when gunshots and screams started coming over the intercom system, according to accounts from the scene.

Twenty children, all ages 5 to 10, and six adults were killed when a masked gunman opened fire inside Sandy Hook Elementary School in Newtown, Conn., authorities said. The gunman was later found dead, a federal law enforcement official told NBC News.

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The brother of a little girl who made it out of the school safely told NBC 30 of Connecticut that his sister told him that her class knew something was wrong "when she heard screams — screams were coming over the intercom and the school went on lockdown."

NBCConnecticut: Newtown massacre: 28 dead

As the children were being led out of the school, state troopers and FBI agents told them to "hold hands and close their eyes until they got outside," said the unidentified young man, "so obviously what was in there must have been very gruesome."

"It truly is disgusting. It's sickening," he said. "Unfortunately, it's a growing trend in the United States."

The Rev. Al Sharpton talks with Kathy Sweeney, whose 8-year-old grandson was at Sandy Hook Elementary School on Friday.

"It was just horrific, and I just found out that a neighbor ... lost a child," said Kathy Sweeney, whose 8-year-old grandson attends the school. 

The boy is doing OK, she told MSNBC, but "I don't think it has set in yet."

Sweeney said her grandson told her that he and his classmates were in a computer room when they were told to duck under their computers.

"The PA system was on, and he said that he heard the gunshots," she said. "And then he said that they were supposed to close their eyes and they made their way up to the firehouse up the street."

See more video on the tragedy at Sandy Hook Elementary on NBCNews.com

Another pupil said everyone "went into a total panic" when they started hearing the gunshots.

"I was going back to my classroom," the boy said. "Then I heard something like a person was kicking on a door. Then I turned around and I saw smoke. ... Then a teacher pulled me into her room."

Asked what his reaction was amid the chaos, the boy said simply, "Whoa."

"You can never be prepared for this kind of incident," an emotional Gov. Dan Malloy said, his voice shaking as he recounted the assault on "a number of our citizens, beautiful children, as well as the adults whose responsibility is to educate those children."

Newtown police Lt. George Sinko called the shootings "definitely the worst thing we have experienced in this town," telling reporters it took officers just minutes after they arrived to recognize "what a horrific scene we had there."

The father of a pupil at Sandy Hook Elementary School describes his feelings upon hearing about the shootings. Then, Colin Goddard, a survivor of the Virginia Tech shootings, reacts to the interview, saying, "We are better than this."

'A powerless and terrifying experience'
The father of a Sandy Hook pupil said he had "no words that I could come up with that could come close to describing the sheer terror of hearing that your son is in a place, or your child is in a place, where there's been violence."

"You don't know the details of that violence. You don't know the condition of your child, and you can't do anything immediately to help them or protect them," he said.

"That is a powerless and terrifying experience."

Sarah W. Caron found a scene of chaos when she arrived to look for her young son. Teachers, police and parents, some of them crying, handed out water and tried to restore some order, she wrote on iVillage.

"The moment I spotted Will's little brown haired head was one of such great relief. I hugged him. I hugged his teacher," Caron wrote. "But this isn't over. My family is safe — thank God — but our school community was shattered today by a horrific tragedy."

A staging area for parents to reunite with their children was set up at the neighboring firehouse.

An elementary school pupil recalls the terrifying moments following sounds of shots at her Connecticut school, saying, "Teachers told us to go in the corner, so we all huddled."

"I was in the gym, and I heard, like, seven loud booms, and the gym teachers told us to go in a corner, and we all huddled, and I kept hearing these booming noises," a young girl said.

"We all started — well, we didn't scream — we all started crying, so all the gym teachers told us to go into the office where no one could find us," the girl said.

"So then a police officer came in and told us to run outside, so we did, and we came in the firehouse and waited for our parents."

"The children who witnessed this are terribly traumatized," said Msgr. Robert Weiss of St. Rose of Lima Catholic Church, who went to the firehouse to offer support and comfort. Weiss' church organized a memorial Mass for 7 p.m. ET.

"They're crying, they're trying to hold on to their parents, they want to go home, but they don't want to leave their friends," Weiss told MSNBC.

"Right now, I'm in a room full of parents who are waiting to hear what happened to their kids," he said. "The anxiety in this room is just overwhelming."

Andrew Mach and Vignesh Ramachandran of NBC News contributed to this report.

For up-to-the-minute coverage of the shootings at Sandy Creek Elementary School, stay with NBCNews.com and tune in to your local NBC station to watch tonight's special report on Dateline NBC.

Neil Culligan and Msgr. Robert Weiss dewcribe the scene outside Sandy Hook elementary School. NBC News' Richard Lui reports.

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