A 26-year-old U.S. citizen has been arrested and accused of plotting to bomb the Pentagon and U.S. Capitol with large remote-controlled aircraft filled with explosives.

Rezwan Ferdaus of Ashland, Massachusetts, the alleged bomber, was arrested Wednesday by undercover federal agents delivering materials he'd requested for his plan, including grenades, machine guns and what purported to be C-4 explosive.

U.S. Attorney Carmen Ortiz said in Boston that Ferdaus was charged with the aerial bombing plot and attempts to deliver bomb- making materials for use in attacks against U.S. troops in Iraq.

According to the federal affidavit, Ferdaus began planning attacks in early 2010. He allegedly believed he would have a large psychological impact by killing Americans.