A 26-year-old U.S. citizen from Massachusetts was arrested as part of an FBI sting operation for concocting a detailed plot to blow up the Pentagon and Capitol buildings, according to The Hill.

Rezwan Ferdaus was arrested and charged today after presenting undercover FBI agents with detailed plans on how to attack the buildings, according to the Department of Justice. He thought he was working with members of al Qaeda.

Ferdaus allegedly spent 5 months compiling the resources needed for the attack — six AK-47's, 25 pounds of fake C-4 explosives, three grenades, and even remote-controlled aircraft — all under the close supervision of undercover FBI agents.

The DOJ emphasized, however, that the plan never posed any danger to the public.

In Ferdaus's plan, three small, drone-like aircraft loaded were supposed to fly into the Capitol and Pentagon while six armed men carried out a massacre on the ground.

"Although Ferdaus was presented with multiple opportunities to back out of his plan, including, being told that his attack would likely kill women and children, the affidavit alleges that Ferdaus never wavered in his desire to carry out the attacks," the DOJ said in a press release today.

When agents told Ferdaus that his phone detonation devices had been used in an attack that killed three U.S. soldiers and injured more, the DOJ says he responded: "That was exactly what I wanted."