Aaron Deshong, a 49-year-old Perkiomen resident, was still on the phone with the FBI's Threat Assessment Center when state police arrived at his Gravel Pike home to take him into custody, said the District Attorney's Office.
The FBI received the call around 5 p.m., according to the criminal complaint released by prosecutors. Deshong allegedly told agents he had been "living on the edge" since his father's death, that he was "not suicidal," and that he "does not trust local law enforcement officers."
He also told authorities his mom and brother were at the home with him but could not come to the phone, the DA's Office said.
"When asked if his mother and brother were unharmed, Deshong kept answering 'That's a good question,'" the documents say.
The FBI alerted state police who arrive just after 5 p.m.
Aaron Deshong was arrested in his garage, while his 74-year-old mother Wanda Deshong and 53-year-old brother Adam Deshong were found shot to death inside, authorities said.
Wanda lived at the home and Adam was a resident of Devon, according to the DA's Office.
The 49-year-old is charged with first-degree murder, third-degree murder, and related counts. He is awaiting his arraignment at the Montgomery County jail and will not be eligible for bail due to the charges, prosecutors added.
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