MADISON, Wis. — The father of a Wisconsin teenage girl who killed a teacher and fellow student in a school shooting was arrested Thursday in connection with the case, an official told The Associated Press.

Police said 42-year-old Jeffrey Rupnow was taken into custody around 3:45 a.m. on May 8. He's being charged with the delinquency of a child and two counts of providing a dangerous weapon to a person under 18 resulting in death. All three charges are felonies, punishable by up to six years in prison each. He was scheduled to make an initial appearance in court on Friday.

The shooting at Abundant Life Christian School (ALCS) on Dec. 16, 2024 left three dead, including Rupnow's daughter, the 15-year-old shooter. 14-year-old Rubi Patricia Vergara and a teacher, 42-year-old Erin Michelle West, were killed by the shooter.

Another six people were taken to the hospital with injuries ranging from “minor” to “life-threatening,” police said. Almost all of those people have been released from the hospital, except for one person that was back in critical condition as of April 1.

Jeffrey Rupnow (Photo Courtesy: Dane County District Attorney's Office)

Jeffrey Rupnow did not immediately respond to a message The Associated Press left on his Facebook page. No one immediately returned voicemails left at possible telephone listings for him and his ex-wife, Melissa Rupnow. Online court records indicate he represented himself in the couple’s 2022 divorce and do not list an attorney for him in that case.

According to a criminal complaint, Jeffrey Rupnow told investigators that his daughter was traumatized by her parents' divorce, saying she hated her life and wanted to kill herself. She had been in therapy to learn how to be more social until the spring before the attack, he told investigators. Her mother, Melissa Rupnow, told detectives that the therapist told her that her daughter was suffering post-traumatic stress disorder stemming from the divorce.

Jeffrey Rupnow said his daughter got into shooting guns after he took her shooting on a friend's land. He said he bought her two handguns and told her the access code to his gun safe was his Social Security number entered backward.

At a press conference Thursday, Madison Police Acting Chief John Patterson said what they found in the search of the home was “disturbing” and “alarming.”

Investigators discovered writings in her room in which she describes humanity as “filth," hated people, got her weapons through her father's “stupidity” and wanted to kill herself in front of everyone. She built a cardboard model of the school and developed a schedule for her attack that ended just after noon with the notation: “ready 4 death.”

Patterson said on the morning of the shooting, the 15-year-old shooter overslept and took a rideshare to school. He said when she arrived, she stopped at her locker, spent time in the restroom and then headed upstairs, opening fire. According to the complaint, investigators recovered 20 shell casings from the study hall where she opened fire.

Police recovered a 9 mm Glock handgun that her father had legally bought her from a study hall where she opened fire and another .22-caliber pistol that her father had given to her as a Christmas present in a bag she had been carrying through the school.

Twelve days after the shooting, a Madison police detective received a message from Jeffrey Rupnow saying his biggest mistake was teaching his kid safe gun handling and urging police to warn people to change the codes on their gun safes every two to three months.

Madison Police Acting Chief John Patterson talks to local media Thursday. (Spectrum News 1/Mandy Hague)

“Kids are smart and they will figure it out. Just like someone trying to hack your bank account.' I just want to protect other families from going through what I'm going through,” he said.

Madison Mayor Satya Rhodes-Conway said at a press conference Thursday that it shouldn't be controversial that children can never have the opportunity to use a gun to harm classmates.

“We need to make our schools sanctuaries for knowledge, not fortresses designed to withstand attack. We need to stop pretending that guns in the home make our children safer, when we know the exact opposite is true," she said.

While Rhodes-Conway said the legislation is needed to address these "horrific" acts in schools across the country, part of the responsibility falls on gun owners.

“Gun owners also have a responsiblity here, the responsiblity to secure their weapons and prevent guns from falling into the wrong hands. If you own a gun, buy a gun lock, get a gun safe and use them," she said.

Jeffrey Rupnow is the latest parent of a school shooter to face charges associated with an attack.

Last year, the mother and father of a school shooter in Michigan who killed four students in 2021 were each convicted of involuntary manslaughter. The mother was the first parent in the U.S. to be held responsible for a child carrying out a mass school attack.

The father of a 14-year-old boy accused of fatally shooting four people at a Georgia high school was arrested in September and faces charges including second-degree murder and involuntary manslaughter for letting his son possess a weapon.

In 2023, the father of a man charged in a deadly Fourth of July parade shooting in suburban Chicago pleaded guilty to seven misdemeanors related to how his son obtained a gun license.

At the end of last month, a Florida man, who was connected to the ALCS shooting, was arrested for allegedly planning a mass shooting and impersonating an officer. Damien Blade Allen allegedly messaged the 15-year-old shooter and also discussed violence online with several others. The two supposedly spoke for months via social media messages.

Read the full criminal complaint here: