'Undoubtedly saved people': teacher fought US shooter

A teacher in the Oregon classroom where a shooter killed three children and an adult threw her mobile phone at the shooter, tackled him and fought him in an act that saved lives, police say.

A day into their investigation of the latest US school shooting, authorities released new details of the scene inside a special needs classroom of Silver Rail Elementary School where three school children aged five, eight and 11 and a teacher were killed by a 16-year-old former student.

Bend Police Chief Mike Krantz did not identify the teacher who fought the assailant, but told a press conference she threw her phone at the suspect, tackled him and fought to take his shotgun from him.

"She was not injured in that incident, but she almost certainly helped prevent more bloodshed," Krantz said.

As the two wrestled, a parent entered the classroom and opened fire on the gunman, killing him.

Officials said the parent had followed the shooter into the school, upon witnessing him firing a shotgun from just outside campus. By the time police arrived within three minutes of receiving their first call, the shooter was dead, police said.

In the meantime the 16-year-old assailant, who had shot through locked glass doors to enter campus, had killed four people and wounded two others.

Krantz, speaking to the heroism shown by the teacher who threw herself onto the suspect and the parent who shot him, said, "I don't think we can underestimate or under-appreciate that courage. When someone is willing to risk their own life for others, we recognise that."

He said the bystander's actions "undoubtedly saved people," and "the teacher who was willing to stand and fight for her children, that's true heroism."

Krantz identified the shooter as Griffin J. John II, who was armed with 12-gauge shotgun. He fired about 15 rounds in the classroom and had another 44 rounds on him.

The parent who killed the shooter was identified as Kaylub Giamanco, his mother told the New York Times. She identified him as the father of two girls who attend the school, according to video posted by the New York Times of Freeman reading a brief statement.

"He is not seeking recognition, but instead wishes to express his gratitude to the first responders, school personnel, and community for the outpouring of love and support," Freeman said.

Residents of Bend, a city of about 100,000 people some 280km southeast of Portland, gathered near the school to mourn on Friday morning, placing flowers and candles just outside yellow crime scene tape that cordoned off the scene.

"Thank God for that father. He saved a lot of lives yesterday, and our prayers should go out for him because he has a lot on his mind today. We wish him well, and thank God for him," Michael Zappa, 71, who lives just blocks from the school, said through tears.