An Oregon elementary school teacher who nearly lost her hand in a horrific mass shooting has revealed how she pretended to be dead in an effort to avoid a fatal shot from the teenage gunman.

Becky Drury, 54, suffered devastating injuries when a 16-year-old former student opened fire at Silver Rail Elementary School in Bend, Oregon, killing three children and another teacher in a terrifying rampage last week.

Now, speaking publicly about the October 15 massacre for the first time, Drury has described the chilling moment she found herself lying helplessly on the classroom floor, unable to move or defend herself after being shot at close range.

Her left hand had been almost completely severed by the gunfire, while her other arm was also badly wounded.

With the shooter still nearby, the injured teacher made a decision to remain completely motionless and hope he believed she was already dead.

'I did the only thing I could do, which was to pretend to be dead in the hope he would not shoot me again,' Drury revealed in an emotional statement on Wednesday.

Her account offers a harrowing glimpse into the violence that unfolded inside the Oregon elementary school, where four people were killed and two others, including Drury, suffered serious injuries.

The attack began when the teenage gunman, identified by authorities as 16-year-old Griffin J. John II, fired through the school's locked entrance doors before making his way inside.

Police said the former student subsequently entered a special needs classroom and began shooting.

Drury recalled hearing a disturbance outside her classroom and rushing to investigate, unaware that she was about to come face-to-face with the attacker.

'I turned to shut the door behind me, but the shooter was already there,' she wrote.

'Before I could do anything more, he shot me at close range and I fell to the ground.'

The sudden attack left her gravely wounded before she had an opportunity to react.

As she lay on the floor, Drury realized the extent of the damage inflicted by the gunfire.

'Lying on the floor, I saw that my left hand was almost completely severed from the gunshot, and my other arm was also severely injured,' she recalled.

'I could not get up, defend myself, or protect anyone else.'

She remained on the floor, pretending to be dead as the attack unfolded around her.

The teacher survived the ordeal, although the injuries she sustained were severe.

Doctors have described her condition as serious but not life-threatening.

Drury's statement comes amid conflicting accounts of what happened inside the school and the actions taken by those caught in the violence.

The wounded teacher said she felt compelled to speak out because she wanted to correct what she described as inaccurate reporting about her conduct during the shooting.

'I want to make sure the events of that day and my actions in particular are reported accurately,' she explained.

She emphasized that the speed of the attack had left her with no opportunity to intervene before she was wounded.

'I know there has been contradictory reporting about my actions that day, but the truth is I was shot before I had any chance to act,' Drury wrote.

Her account makes clear that she was incapacitated almost immediately after encountering the gunman, leaving her unable to protect herself or anyone else.

She also paid tribute to the families and wider school community whose lives have been shattered by the killings.

'What happened in that classroom was unimaginable, and like so many in this community, my heart is broken for everyone affected by this tragedy,' she said.

A GoFundMe has been set up to help pay for her medical bills. 

The massacre claimed the lives of three young children, ages five, eight and eleven, along with a 25-year-old teacher. A seven-year-old student was also seriously injured in the shooting.

The identities of the victims and the circumstances surrounding their deaths have left the Bend community struggling to comprehend the scale of the tragedy.

The gunman, who had previously attended Silver Rail Elementary, was eventually confronted as the attack unfolded.

An armed bystander, 36-year-old Kaylub Giamanco, followed the shooter into the school and subsequently shot him dead, bringing the rampage to an end.

Investigators have identified John as the person responsible for the attack, although authorities have not established a motive in the information released publicly.