The unnamed 17-year-old boy was taken into custody at his Wynnefield residence after an investigation by Bureau agents, Philadelphia police, and various federal agencies, according to District Attorney Larry Krasner's Office.
Authorities said that an Instagram account connected to the West Philly teen had communicated with an account affiliated with Katibat al Tawhid wal Jihad (KTJ). The State Department has said KTJ is "affiliated with al-Qaida" and named the group a "Specially Designated Global Terrorist" last March.
KTJ operates mostly in Syria's Idlib Province, but the State Department has claimed the group carried out deadly attacks overseas, including a Russian metro attack in 2017 and a 2016 Chinese Embassy bombing in Kyrgyzstan.
In addition to Instagram, authorities say the teen used photos of the ISIS banner and a Chechnya-based terrorist group as his profile pictures on WhatsApp.
Agents claimed they watched the teen buy "materials that can be used to make IEDs," or homemade bombs, on Aug. 7. They also claimed that US Customs and Border Protection logged records of "military and tactical gear" being shipped to his home from overseas.
“Self-radicalization by young people via the internet is a threat to all families," said DA Krasner, whose office is charging the 17-year-old with weapons of mass destruction, criminal conspiracy, and related felonies.
"Parents: Keep an eye out for violent cults that would lure in your kids under the guise of politics or religion," Krasner said.
If the teen is charged as an adult, "more information related to the allegations against him will be available to the public," authorities added.
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