MADISON, Wis. — A 15-year-old student opened fire inside a study hall at a small Christian school in Wisconsin, killing a teacher and a teenager and prompting a swarm of police officers to descend on the school in response to a second grader’s 911 call.

The girl also wounded six others in Monday’s 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.

‘‘Every child, every person in that building is a victim and will be a victim forever. … We need to figure out and try to piece together what exactly happened,” Barnes said.

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. Barnes declined to offer additional details about the shooter, partly out of respect for the family.

Abundant Life is a nondenominational Christian school — prekindergarten through high school — with approximately 420 students in Madison, the state capital.

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.

Wiers said the school does not have metal detectors but uses other security measures including cameras.

Fravel was seen driving Kingsbury’s minivan down Hwy. 43 later that morning. He told police he was dropping items off at his parents’ house in Mabel, where he planned to move that weekend, but turned around after he saw items in the back that he wanted to put in a storage unit across from his and Kingsbury’s house in Winona.

Video camera footage shows Fravel driving Kingsbury’s van along the highway but doesn’t account for him for about 45 minutes after he passed through Choice Township.

Kingsbury was found on 198th Street a half-mile off Hwy. 43, on property Fravel’s father maintained for a time. A medical examiner later said she died of homicidal violence by asphyxiation, though the body was too decomposed to find further evidence.

Police shot and wounded a man with a knife in northwestern Wisconsin, state officials said Tuesday.

The incident occurred shortly before 6 p.m. Monday roughly 12 miles southeast of Webster in Burnett County, according to the Wisconsin Department of Justice’s Division of Criminal Investigation (DCI).

The DCI has yet to identify the suspect, who was taken by air ambulance to a hospital in Minnesota for treatment. Officials have not said how seriously he was injured.

St. Croix tribal police officers responded to a domestic incident at a home in the Town of Webster in the 24000 block of Eagle Feather Drive. Upon arrival, they encountered a man with a knife, and one of the officers shot him.

The DCI did not address what threat the man may have posed to himself or others before he was shot.

The officers involved in the incident were put on standard administrative leave.

Several agencies are assisting the DCI with its investigation including the Minnesota Bureau of Criminal Apprehension (BCA). The DCI has yet to say why the BCA is involved in the case.