Mohn, 32, of Levittown, was previously accused of killing his federal employee father at his Middletown home, beheading his corpse, and uploading the grisly footage to YouTube on Jan. 30.
In the video, authorities said Mohn called for "all militia and patriots across the United States to kill all federal employees." His father Michael Mohn worked for the US Army Corps of Engineers, they noted.
The younger Mohn was arrested that night after police traced his location to the Pennsylvania National Guard Headquarters at Fort Indiantown Gap. At the time, police said he was armed with a loaded 9mm handgun and had hopped a barbed wire fence to gain entry.
The 32-year-old was charged with first-degree murder, abuse of a corpse, and possession of an instrument of crime on the night of his arrest.
Now, prosecutors say he is also charged with two additional counts of possession of an instrument of crime, and one count each of robbery, firearms not to be carried without a license, theft by unlawful taking, receiving stolen property, criminal use of a communication facility, terroristic threats, and defiant trespassing, in addition to the three terrorism counts.
Authorities said they believe Mohn traveled to the Fort Indiantown Gap "in an effort to mobilize the National Guard to raise arms against the federal government." A USB flash drive in his possession "contained several pictures of federal buildings along with instructions that appeared to show the steps needed to make an explosive device," they added.
Mohn is being held without bail at the Bucks County Correctional Facility and has a preliminary hearing scheduled for April 2, according to court records.
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