The teen gunman who killed at least three children and an adult at an Oregon elementary school was shot dead by a hero bystander, law enforcement sources said.

The bystander sprang into action just minutes after the police received their first report of a shooting at Silver Rail Elementary School in the city of Bend, according to sources and police.

The first call placed to dispatchers indicated that a shot had been fired into a car near the school, police spokesperson Sheila Miller told reporters.

At least three kids and one adult, believed to be a teacher, were gunned down by the teen.

Two other children have also been hospitalized in unknown condition, according to preliminary information from law enforcement sources.

Roughly 400 to 450 children attend the school, which was evacuated after the terrifying shooting.

It’s not immediately known where the shooting unfolded, or whether the bystander was permitted to have a gun near the elementary school’s campus.

Bend La Pines school district previously banned all people, including those with concealed handling licences, from carrying firearms on district property, Oregon Public Broadcasting reported in 2022.

A separate provision of state law does allow lawfully possessed guns on school grounds if they are unloaded and locked in a vehicle, the outlet reported.

Local officials are expected to hold another press conference with additional details around 8:30 p.m. EST.