Justin Mohn had purchased the gun, a 9mm SIG Sauer pistol, the day before he allegedly killed 68-year-old Michael F. Mohn at their shared home, said Bucks County District Attorney Jennifer Schorn at a Friday press conference.
Investigators believe Mohn, 32, shot his father in the head before dismembering him, the DA said. The younger Mohn was gone when police arrived at their Upper Orchard Drive residence in Middletown, she added.
His cell phone was eventually tracked to Fort Indiantown Gap, where the Pennsylvania National Guard is headquartered, the DA said. Mohn jumped a barbed wire fence and was inside the base when police found him, authorities said.
Schorn said Mohn hoped to "mobilize the Pennsylvania National Guard to raise arms against the federal government" and wanted to convince Governor Joshua Shapiro to "join forces" with him.
About an hour before his father's body was discovered Tuesday, Mohn posted a YouTube video titled "Mohn's Militia - Call To Arms For American Patriots," Daily Voice reported.
In the video, Mohn identifies himself and says that he killed his father, ranting about the government and wearing rubber gloves showing his father's head in a plastic bag, according to police. He also called for the killing of federal government employees, the DA said.
The video had been viewed more than 5,000 times before it was removed from the platform.
Mohn allegedly fled the scene in his dad's 2009 Toyota Corolla before his mom found the corpse. He has been charged with first-degree murder, abuse of a corpse, and related counts.
The case remains under investigation, Schorn added.
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