HAMILTON, Canada/ISTANBUL

A shooting Wednesday at a high school in the US state of Colorado left the student shooter dead and two others critically injured, according to a local report.

Citing the Jefferson County Sheriff's Office, the report by ABC News said the incident took place at Evergreen High School shortly after midday.

The injured students were transported to St. Anthony Hospital, where one remains in critical condition, the report added.

The suspected shooter, whose identity has not been revealed by authorities, died of a self-inflicted gunshot wound.

"I don't know if our suspect is even old enough to drive," said Jefferson County Sheriff's Office spokesperson Jacki Kelley.

The sheriff's office said the suspect was armed with a revolver.

In a statement, Colorado Gov. Jared Polis said he was devastated by the shooting.

"My heart goes out to the victims and their families as they grapple with this senseless act of violence," Polis said.

After the shooting, hundreds of police officers were on the scene searching each room on campus, according to law enforcement.