A girl (2nd R) cries after placing flowers and balloons on a fence outside Marysville-Pilchuck High School as people mourn the day after a shooting at the school in Marysville, Washington October 25, 2014. [Photo/Agencies]

All five victims were under 18, medical officials said.

One female classmate was killed, police said. Her identity has not been released.

Fifteen-year-old Andrew Fryberg was shot in the head and remained in critical condition in intensive care at Harborview Medical Center in Seattle on Saturday, a spokeswoman said. She said Nate Hatch, 14, was shot in the jaw and was in serious condition there.

Local media, community members and fellow students said the boys were cousins of the shooter.

Brandon Hatch, 26, a first cousin of Nate Hatch, said Andrew Fryberg and Nate are cousins of Jaylen, and the other victims were friends.

"As far as I knew they were all a bunch of bright kids and had a future," he said. :I've heard rumors but can't state fact on what provoked this. I'm just confused at this moment."

The two female victims, Shaylee Chuckulnaskit, 14, and Gia Soriano, 14, remained in critical condition Saturday at Providence Regional Medical Center in Everett, said Dr. Joanne Roberts.

"The next three days are going to be crucial," she said.

The sheriff's office said a cafeteria worker had attempted to stop the shooter, who took his own life.

Vigils were planned through out the weekend.

Misty Himes, 30, drove with her friend to pick up her son after the shooting.

"Everybody is just torn up to see the kids so young have to go through this," she said.

There were no indications on Fryberg's social media accounts that he had been planning such a rampage, but on Tuesday he posted his feelings of despondency, apparently over a romantic split, on Twitter.

"It breaks me...It actually does...I know it seems like I'm sweating it off... But I'm not.. And I never will be able to," he wrote.

Classmates said they were shocked that mass violence had come to their city.

Karalyn Demarest, 17, a senior at Marysville, added a bouquet of flowers to nearly a dozen that were lying against a fence at the school.

"It's just really sad and tragic. You just never expect it to happen anywhere near you."