A Philadelphia teenager was plotting a national attack with members of the global terrorism group Katibat al Tawhid wal Jihad, which is affiliated with Al Qaeda, and had access to a "significant" number of guns and was working on building a bomb, authorities said.
The 17-year-old, who wasn't named during Monday's press conference, was arrested and faces a litany of charges, including possession of weapons of mass destruction and terrorism.
He was in the process of building improvised explosive devices with several undisclosed targeted locations "that were not just in Philadelphia," FBI Special Agent in Charge Jacqueline Maguire said during Monday's press conference.
"Most concerning was the evidence to his access to firearms and was purchasing items and materials commonly for constructing improvised explosive devices," Maguire said. "Among the items he purchased were tactical equipment, wiring, chemicals and devices often used as the detonators."
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The purchases were made in the last couple of weeks, which quickly escalated this case, Maguire said.
Armored police vehicles and tactical teams swarmed the teenager's West Philadelphia home Friday.
The sprawling operation with FBI agents and heavily armed law enforcement closed off areas of the Wynnefield section of the city for parts of the weekend.
For almost 72 hours, it was officially described as a "court-authorized law enforcement activity" without providing any other details or context, which gave area residents a sense of unease.
Neighbors told ABC 6 that law enforcement officers were seen patrolling the area for weeks, even months, before swarming the home on Woodbine Avenue.
"The degree of the response, again I was out when it happened, but seeing the pictures, they had armored vehicles and so forth. Seems like the FBI was preparing to experience some violent response or something," David Hauck told the local news outlet.
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