A 20-year-old man from Carlsbad, California, has been detained after allegedly communicating with the teenage shooter who killed two people at Abundant Life Christian School in Madison, Wisconsin, on December 16.
Authorities say Alexander Paffendorf had been in contact with 15-year-old Natalie Rupnow, the shooter, and the two reportedly discussed planning a mass attack.
According to court documents obtained by PEOPLE, Paffendorf confessed to FBI agents that he had shared his plans with Rupnow.
He allegedly told her that he intended to “arm himself with explosives and a gun” to target a government building.
The FBI says the two had exchanged messages about their violent intentions before the deadly shooting at the Wisconsin school.
Following the discovery, a gun violence emergency protective order was issued against Paffendorf, requiring him to surrender all firearms and ammunition within 48 hours.
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He was detained by police on December 17, but it remains unclear if formal charges have been filed. A court hearing is scheduled for January 3, 2024, to review the protective order.
The shooting at Abundant Life Christian School resulted in the tragic deaths of Erin M. West, 42, and Rubi Patricia Vergara, 14. Six others were injured, some seriously.
Rupnow, who went by the name “Samantha,” reportedly shot herself after carrying out the attack. Authorities have yet to determine a clear motive for the shooting, but Rupnow’s family is cooperating with the investigation.
Neighbors of Paffendorf have expressed shock, with one neighbor stating, “That’s not good. That’s scary,” after learning about the arrest.
Authorities are continuing to investigate both Paffendorf’s involvement and Rupnow’s motives behind the deadly attack.