New York City
New York CityThinkstock

A former New York City high school teacher and his brother were arrested on Thursday and charged with attempting to build an explosive device after an investigation by the FBI, authorities said, according to Reuters.

Christian Toro, the former teacher, and his brother Tyler Toro, both 27, had stockpiled materials for making bombs in the apartment they shared in the Bronx, according to a criminal complaint and a news release from the Department of Justice.

Christian Toro was a teacher at a high school in Manhattan's Harlem neighborhood before resigning last year. When he left the job, Toro returned a computer that had been provided by the school, and staff found instructions on it for building explosive devices, according to the complaint.

Investigators found that at least two students at the school had been paid about $50 an hour to break apart fireworks and store powder for the two men, the complaint said.

A search of the apartment found potassium nitrate, black powder identified as an explosive material, metal spheres and other bomb components, the document said, according to Reuters.

Law enforcement agents found a backpack with an index card reading, "Under the full moon the small ones will know terror," the complaint said.

The two brothers have been charged in federal court in Manhattan. Christian Toro was charged with two counts of unlawful manufacture of a destructive device and distribution of explosive materials to a minor. Tyler Toro was charged with unlawful manufacture of a destructive device.

Both men have pleaded not guilty and are being detained pending a bail hearing on February 21.

New York has been targeted by two terrorist attacks in recent months. On December 11, Bangladeshi immigrant Akayed Ullah detonated a crude pipe bomb packed with screws in a subway passageway near Port Authority Bus Terminal during the morning rush hour. Luckily, he was the only person seriously injured in the blast.

On October 31, Uzbekistan-born Sayfullo Saipov drove a rented truck onto a Lower Manhattan bike path that was packed with pedestrians, killing eight people and injuring 12 others.

Since 2013, American prosecutors have charged more than 100 radicalized individuals with terror-related crimes.