A 15-YEAR-OLD student opened fire inside a study hall at a small Christian school in Wisconsin, killing a teacher and teenager on Monday.

The girl also wounded six others in the shooting at Abundant Life Christian School, including two students who were in critical condition, Madison Police Chief Shon Barnes said.

A teacher and three students were taken to a hospital with less serious injuries, and two of them were later released.

Police said the shooter, identified as Natalie Rupnow, was found with a self-inflicted gunshot wound when officers arrived and died en route to a hospital.

Mr Barnes declined to offer additional details about the shooter.

Barbara Wiers, the school’s director of elementary and school relations, said when they practice safety routines, leaders always announce that it’s a drill. That didn’t happen Monday, just a week before Christmas break.

“When they heard, ‘Lockdown, lockdown,’ they knew it was real,” she said.

A motive for the shooting was not immediately known, nor was it clear if the victims were targeted, Mr Barnes said.

In a statement, US President Joe Biden cited the tragedy in calling on Congress to pass universal background checks, a national red flag law and certain gun restrictions.

“We can never accept senseless violence that traumatises children, their families, and tears entire communities apart,” Mr Biden said.

The school shooting is the latest across the US in recent years, including especially deadly ones in Newtown, Connecticut, Parkland, Florida and Uvalde, Texas.

The shootings have set off fervent debates about gun control and frayed the nerves of parents whose children are growing up accustomed to doing active shooter drills in their classrooms. But school shootings have done little to move the needle on national gun laws.

Firearms were the leading cause of death among children in 2020 and 2021, according to KFF, a nonprofit that researches healthcare issues.