denver shooting
All the victims were aged 15 or older.Twitter

An 18-year-old student was killed and seven others were critically injured in a shooting incident on Tuesday (May 7) at a suburban Denver school near the capital of the US western state of Colorado.

"It is with extreme sadness that we can confirm that one student at the STEM School was killed in today's #stemshooting incident. The immediate family has been notified. Douglas County Coroner Jill Romann has not officially identified the student stating it's an 18-year-old male," the Douglas County Sheriff's Office said on Twitter.

Two male students were apprehended after the shooting at the STEM School in the Highlands Ranch area. Addressing a press conference, Douglas County Sheriff Tony Spurlock said that the two shooters walked into the school and opened fire on students in at least two classrooms. "Two suspects entered the school just before 2 pm (local time) and got deep inside the school and engaged students in two separate locations," according to Douglas County Sheriff Tony Spurlock.

The sheriff said a number of students were shot and wounded; all the victims were aged 15 or older.

A handgun and the suspects' vehicle have been recovered by the police. As of now, no information has been shared on any other weapons that may have been used.

School shootings have since become a frequent occurrence in the US, where firearms killed nearly 40,000 people in 2017, according to the Centers for Disease Control and Prevention.

Since Columbine, an estimated 226,000 children in 233 schools have been exposed to the sight or sound of gunfire, according to a Washington Post investigation.

The worst shootings to date were those at Sandy Hook Elementary School in Newton, Connecticut in 2012 (20 young children and six adults were killed) and at Marjorie Stoneman Douglas High School in Parkland, Florida last year (17 dead).

The number of firearms in circulation has continued to grow (now at 393 million in a nation of 326 million people), and mass shootings have become a disturbingly regular part of American life.