Philadelphia teen charged with planning national terrorist attack

Heavily armed law enforcement officers swarmed the Philadelphia home of a teenager who was plotting to launch a national terrorist attack, authorities said.

The suspect, an unnamed 17-year-old, was in contact with a global terrorist group affiliated with al Qaeda and had access to a "significant" number of guns and was building bombs, FBI Special Agent in Charge Jacqueline Maguire said during a Monday press conference.

The teen, who was arrested Friday, "conducted general research" into potential targets that weren't confined to one location, and they were not just in Philadelphia, she said.

"Most concerning was the evidence to his access to firearms and purchased items and materials commonly [used] 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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These purchases were made within the last few weeks, which quickly escalated this case "in both threat and priority," she said.

Investigators monitored the suspect's activity after learning he was in contact with the terrorist group Katibat al Tawhid wal Jihad (KTJ), an al Qaeda-affiliated group that primarily operates in the Idlib province in Syria.

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He allegedly sent and received media to and from the KTJ on Instagram in March and April that contained terrorist propaganda and guidance on committing to criminal acts, including how to construct a bomb.

He "appeared to be taking steps to travel overseas for the purpose of joining or supporting terrorist activity," she said.

The suspect wasn't named because of his age and is currently facing state charges, although both of those will likely change, Philadelphia District Attorney Larry Krasner said.

The charges are weapons of mass destruction, criminal conspiracy, arson, causing or risking catastrophe, attempt to commit criminal mischief, possession of an instrument of crime and reckless endangerment of another person, Krasner said.

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His office will file a motion to prosecute the suspect as an adult, and the charges could be escalated to the federal level, Krasner said. To date, only the 17-year-old has been charged.

"The charges we have filed against this individual represent the most serious alleged terrorist activity prosecuted in Philadelphia County court in recent history," Krasner said in a statement after the arrest.

"We intend to pursue full accountability for these crimes and will continue to work vigilantly with our law enforcement partners to protect all of our communities from hateful, ideologically driven acts of violence."

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Authorities were peppered with questions about his parents and if they're cooperating, but authorities sidestepped those questions as well as questions about when the suspect began communicating with KTJ, citing the ongoing investigation.

Maguire's answers were vague, but she said it was "just a matter of weeks" from the time they started surveillance to this weekend's raid.

She didn't answer questions about how the suspect came in contact with the terrorist group, but the 23-year counterterrorism veteran said this case is an example of the frightening shift in radicalizing Americans.

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"It used to be that years ago you'd have to travel overseas to go to training camps, and that's not the case anymore because you can very easily sit at home, sit in this country and be radicalized on the internet," Maguire said. "The threat has changed, and it's changed drastically over the past couple of decades.

"What hasn't changed is these foreign terrorist organizations, again, having their sights set on America and being willing to not only recruit people from within this country but to target our citizens and our equities and interest here, too."

Timeline of events

Federal investigators, including the FBI Joint Terrorism Task Force, began monitoring the suspect's activity while he communicated with KTJ on Instagram.

A WhatsApp account linked to the suspect's phone number had banner of Riyad-us-Saliheen Martyrs’ Brigade, a Chechnya-based terrorist group, as its profile photo.

That was changed on Aug. 6 to an image of the ISIS banner, according to a press release by Krasner.

On Aug. 7, FBI special agents observed him buying materials to make IEDs and recovered those items from his household trash.

On Aug. 8, U.S. Customs and Border Protection flagged 14 international shipments of military tactical gear to the suspect's home.

On Aug. 11, a warrant for the teenager's arrest was approved and two residences tied to him were searched.

Executing the raid and weekend of unease

Armored police vehicles and tactical teams surrounded the teenager's West Philadelphia home Friday.

The sprawling operation with FBI agents and heavily armed law enforcement officers guarded the 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.

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"The degree of the response, again, I was out when it happened, but seeing the pictures, they had armored vehicles and so forth," David Hauck told the local news outlet over the weekend.

"Seems like the FBI was preparing to experience some violent response or something."

What Is Katibat al Tawhid wal Jihad (KTJ)

KTJ was officially designated as a worldwide terrorist group in 2022 by the State Department, and it was added to the U.N. Security Council's ISIS and al Qaeda sanctions list.

It operates primarily in the Idlib province of Syria, alongside Hay’at Tahrir al-Sham, and cooperates with other designated terrorist groups such as Katibat al-Imam al-Bukhari and Islamic Jihad Group, according to the State Department.

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The group carried out the suicide bombing on the St. Petersburg, Russia, metro in April 2017 that killed 14 people. A second bomb was diffused before detonation.

The KTJ also executed a suicide car bombing of the Chinese Embassy in Bishkek, Kyrgyzstan, in August 2016 that wounded three people.