The December 16 shooting at Abundant Life Christian School in Madison, Wisconsin, left two students dead and six others injured, while the suspected shooter, 15-year-old Natalie Rupnow, died from a self-inflicted gunshot wound. Authorities are investigating to determine her motives.

As reported by The Associated Press (AP), Madison Police Chief Shon Barnes stated that investigators are working to understand the reasons behind the attack. “Identifying a motive is our top priority, but at this time it appears that the motive is a combination of factors,” he said.

The shooter used a handgun in the attack, and police are working to determine how she obtained the weapon. Barnes also confirmed that investigators are examining whether the firearm was owned or possessed by her parents.

“We also want to look at if the parents may have been negligent. And that’s a question that we’ll have to answer with our district attorney’s office,” Barnes said. “But at this time, that does not appear to be the case.”

Police are also speaking with Rupnow’s father to gather information about his knowledge of the events leading up to the shooting and whether he was aware of any warning signs or plans. Barnes noted the difficulty of the situation, “But again, he lost someone as well.”

Investigators believe Rupnow was already inside the school when the attack began and have confirmed that no security breach occurred.

According to the AP, the attack injured six people, including two students. CNN also reported that a substitute teacher was among the injured, and a full-time teacher was one of the two killed.

When asked if Rupnow deliberately targeted her victims, Barnes said, “We don’t know if there would be a reason to target a (substitute) teacher, in this case, who doesn’t have significant ties to the school.”

Besides talking to Runpow’s parents, police are analyzing Rupnow’s electronic devices, which have been turned over to FBI technicians, to determine if she communicated her plans or warned anyone about the attack. “There are always signs of a school shooting before it occurred. We’re looking into her online activity,” Barnes said.

Daniel Brunner, a retired FBI supervisory special agent, suggested the importance of addressing potential missed warning signs. “If they missed a red flag and chose not to address it, if she made overt actions and overt statements that she wants to kill and they didn’t do it, that should be considered too,” he remarked.

The tragedy has left the Abundant Life Christian School community in shock. The nondenominational school, serving prekindergarten through high school, has about 420 students.

Madison Mayor Satya Rhodes-Conway and Dane County Executive Joe Parisi declined to name the victims, citing privacy concerns. “Leave them alone,” Rhodes-Conway said during a press conference.

Outside the school, community members have begun paying tribute to the victims. Mackenzie Truitt, whose brother graduated from Abundant Life, placed a red poinsettia at the entrance. “My heart sunk because I know how awesome a lot of these kids are,” Truitt shared.

Truitt described the widespread fear during the shooting, highlighting the distress of not being able to contact loved ones. She called the experience deeply unsettling for everyone involved.

Police continues to investigate the motives behind the Abundant Life Christian School shooting while the grieving community seeks answers and healing.