The suspect, Muhyee Ud-Din Abdul-Rahman, who was 17 years old when he was arrested in August 2023, has been moved from juvenile court to adult court.
Authorities say he had a scholarship to college, but instead he wanted to move to Syria and make bombs for terrorists.
He got his passport two weeks before his arrest.
"They are wondering how he he became radicalized," said First Assistant DA Robert Listenbee.
Law enforcement began investigating Rahman in March of 2023 after they received electronic communications between the defendant and terrorist organizations in Syria with ties to Al Qaeda.
Investigators found ingredients for bombs in his trash can while under surveillance, prompting his arrest.
Authorities say the suspect was stockpiling weapons and testing TATP bombs in his neighborhood in the 5900 block of Woodbine Avenue in Wynnefield and in nearby Morris Park.
"If there had been a bomb explosion in the neighborhood, his home, or in the woods, it would have had a catastrophic impact on the community," said Listenbee.
17-year-old arrested in Philly in connection with terrorism probe
A warrant was also served at another relative's home in the 1200 block of Wallace Street.
Investigators say Abdul-Rahman used his cellphone to search for information on possible targets, which included the Pride Parade and the LGBTQ community.
Other potential targets included nuclear power plants in Salem, New Jersey and Limerick, Pennsylvania; the Army-Navy Game; and many more in some 8,000 searches by the suspect.
"After careful consideration, it was concluded he was at least considering targeting the LGBT community and the Pride Parade. That did not happen," said Listenbee.
Still, Listenbee said, prosecutors thought it was important to acknowledge that was one of the "intense searches" that occurred.
Authorities say Abdul-Rahman also tried to recruit people , but no one else has been charged. One person it appears he was in contact with, turned him down.
Bail was set at $5 million, the D.A.'s office said Wednesday.
Abdul-Rahman could face 24 to 48 years in prison.