Story highlights Students, parents and school leaders gather to remember

Friends of the slain student identify her as Zoe Galasso

Student witness says teacher "ran towards shooter" to stop him

Four students remain hospitalized after the shooting last week

The teenage gunman who opened fire in a high school cafeteria in Washington state last week may have had more victims had it not been for the bold actions of a young teacher.

Witnesses say Jaylen Fryberg , a popular freshman, shot and killed a female student and wounded four others in the crowded lunchroom at Marysville-Pilchuck High School on Friday, about 34 miles north of Seattle.

Megan Silberberger, a teacher, was in a nearby office when she heard the shots, said Randy Davis, president of the Marysville Education Association.

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Photos: Photos: Shooting at Washington high school Photos: Photos: Shooting at Washington high school Shooting at Washington high school – Students from Marysville-Pilchuck High School write messages and prayers during a vigil Friday, October 24, at a church in Marysville, Washington. Earlier in the day, a student shot five people at the school before he committed suicide, law enforcement officials told CNN. Hide Caption 1 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – Community members and students gather for the vigil. Hide Caption 2 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – People embrace at the church where students were taken to be reunited with parents. Hide Caption 3 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – Parents crowd around buses as students arrive at the church. Hide Caption 4 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – A woman waits on a curb at the church. Hide Caption 5 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – People hug after arriving at the church. Hide Caption 6 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – A girl is consoled at the church after the shooting. Hide Caption 7 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – Police monitor the school's athletic fields after the shooting. Hide Caption 8 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – Emergency personnel respond to the school after the shooting. Hide Caption 9 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – Authorities "are confident that there is only one single shooter," Marysville police spokesman Robert Lamoureux told reporters. Hide Caption 10 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – Students walk across a field after reports of shots being fired at the school. Hide Caption 11 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – Authorities first learned about the shooting after getting a 911 phone call around 10:30 a.m. (1:30 p.m. ET) from someone inside the school, Lamoureux said. Hide Caption 12 of 13 Photos: Photos: Shooting at Washington high school Shooting at Washington high school – A student locked down inside a classroom told CNN by phone that the shooting began in the cafeteria. Hide Caption 13 of 13

"She ran into the cafeteria and saw students down," said Davis. Silberberger also saw a gunman.

"She ran towards the shooter," he said, "to stop... and help secure (him)."

Davis would not reveal details of the confrontation, but one student who witnessed it told CNN affiliate KIRO what he saw

"She just grabbed his arm," said Erick Cervantes. "She's the one that intercepted him with the gun. He tried either reloading or tried aiming at her."

"I believe she's actually the real hero," Cervantes said.

Silberberger declined CNN's request to be interviewed but issued this statement: "I am thankful and grateful for the support from everyone. At this time I am requesting privacy."

A law enforcement source with knowledge of the investigation told CNN that Fryberg was indeed having trouble reloading and that it was because his hands were trembling.

Police have not yet said how many shots in total were fired, but there was at least one bullet left in the cartridge before the confrontation with Silberberger -- because the final shot was the one that ended Fryberg's life. A Beretta .40-caliber handgun believed used in the shooting has been traced to Fryberg's father, according to the source.

Victims weren't random

Students, parents and school leaders met inside the gym at Marysville-Pilchuck High School on Sunday to remember, mourn and talk about ways to move forward. Students and parents were separated for private discussions.

Authorities have not publicly released the name of the female student killed, however, her friends have identified her to CNN as Zoe Galasso.

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Zoe Galasso in a photo from Facebook.

The wounded -- two girls and two boys -- are in intensive care in hospitals in Seattle and Everett. Among them are members of Fryberg's own family.

Andrew Fryberg, 15, is in critical condition, and Nate Hatch, 14, in serious condition at Harborview Medical Center in Seattle, according to hospital spokeswoman Susan Gregg.

"All three of them are cousins, and they live right close to each other," Don Hatch, Nate's grandfather, told CNN affiliate KOMO

The boys were close friends, nearly inseparable, Hatch said. They even went to a school dance together recently, where Fryberg was named the freshman class homecoming prince.

"Only God knows what escalated this. Only God knows," Hatch said, according to KOMO . "Nobody pushed a button with bullying. It's just something that happened, and we don't know why."

Hatch said he forgives Fryberg and plans on visiting his family.

"I'll say, 'I feel for you and I'll pray for you,' " he said.

The girls were identified as Shaylee Chuckulnaskit and Gia Soriano, both 14, according to Dr. Joanne Roberts, Providence Regional Medical Center Everett's chief medical officer. They were in critical condition with head injuries.

At a news conference Saturday, Roberts read a brief statement from Soriano's family: "Our family is in shock. We appreciate your thoughts and prayers during this tragedy. Our hearts go out to the other victims and their families."

Lunchroom in shock

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Investigators in Marysville have not provided details, but students offered up accounts that painted a terrifying, chaotic picture.

Fellow student Jordan Luton was finishing his lunch in the cafeteria when he heard a loud bang.

He saw Fryberg go up to a table of students, "came up from behind ... and fired about six bullets into the backs of them," Luton told CNN. "They were his friends, so it wasn't just random."

According to a law enforcement source, witnesses said Fryberg pulled the gun out of a black backpack before he began firing.

Witnesses described the look on his face as calm, said the source.

Grief, disbelief

It was hard for Luton to make sense of the shooting.

"I have no idea what his motive was because yesterday at football practice, he was all fine, talking ... having a good time," he said. "And then today, just horrible. I don't know what went through his head or what caused him to do it."

By all accounts, Fryberg was a popular student. Just a week ago, he had been named the high school's freshman homecoming prince, according to a YouTube video of the ceremony and accounts provided by students to CNN.

"It's weird to think about, because you see him and he is such a happy person," sophomore Alex Pietsch said. "You never really see him be so angry and so upset. ... People were telling me who it was when I was getting in my mom's car and I was like, 'What? This is not happening. ... This is crazy.' It was just surprising to me that him out of all people would be the one."