This post has been corrected. See the note at the bottom for details.
NEWTOWN, Conn. -- After the gunfire subsided, some of the children ran out of the school to safety. Others walked in a single-file line, hands on each other’s shoulders, as if they were heading to lunch.
Then they leaped into the arms of tearful parents and recounted their morning of terror at Sandy Hook Elementary School, where a gunman killed 26 people, including 20 students, authorities said.
Some of the children heard the shots, which one student described as sounding like someone kicking in a door.
PHOTOS: Connecticut school shooting
A third-grader named Alexis told CNN she looked out the window, spotted police officers and heard footsteps on the school roof.
Some of the students were so upset, she said, "they got a stomachache."
A fourth-grade boy was in the gym when he heard pops and bangs.
“We thought it was the custodian knocking stuff down,” he told CNN. “We heard screaming … and then the police came in and said, ‘Is he in here?’”
The children were herded into a gym closet, the fourth-grader said, and huddled there until police told them it was safe to leave.
The gunman, identified as Adam Lanza, 20, died at the scene. His mother, Nancy Lanza, worked at the school, which has about 600 students and sits at the end of a two-lane road lined with barns converted to houses.
As of mid-Friday, the campus bore the sadly familiar hallmarks of a mass casualty event: Firetrucks rumbling. News helicopters whirring. A woman, face streaked with tears, screaming into her cellphone.
Authorities carrying what appeared to be assault rifles swarmed the area. One bystander told CBS that he saw authorities yank a man out of the nearby woods and handcuff him.
The man made eye contact with some bystanders and, according to the witness, said: “I did not do it.”
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John Thompson, 36, who lives near the school, saw his once-quiet street transformed into a pathway for people running to find out what happened to loved ones. They included Janice Markey, who was walking briskly.
Her best friend's daughter goes to the school, and she doesn't know where the girl is, Markey said. She fought back tears.
For the Record, 2:16 p.m. PST Dec. 14: Officials have corrected the identity of the gunman in Friday’s deadly shooting at an elementary school in suburban Connecticut, saying the suspect was Adam Lanza, 20, and not his brother, Ryan. Ryan Lanza was being questioned by authorities, sources said. The Times, citing unnamed sources, previously reported that Ryan was the suspect.
Semuels reported from Newtown and Powers from Los Angeles. Times staff writers Robin Abcarian, Marisa Gerber and Andrew Khouri contributed to this report.