Emir Balat, the 18-year-old Muslim from Pennsylvania charged with terrorism for throwing two homemade bombs into a anti-Muslim crowd near Gracie Mansion on Saturday, reportedly bought the fuse used in the devices at Phantom Fireworks in Penndel, a Philadelphia suburb, on March 2.

Surveillance footage shows Balat, who says he was inspired by ISIS, entering the store at 12:46 p.m. that day and shopping. Inside video captures him purchasing a 20-foot roll of safety fuse, a thick, twine-like material later used in the bombs.