The FBI have arrested an American citizen accused of plotting to fly explosive-packed remote controlled planes into the Pentagon and the US Capitol building in Washington DC.
The 26-year old physics graduate, Rezwan Ferdaus, is also charged with attempting to supply material to al-Qaeda.
He was arrested on Wednesday in Ashland near Boston after an undercover operation by the FBI.
In January the suspect allegedly told the agents he planned to attack the Pentagon using small drone aircraft filled with explosives and guided by GPS.
The US Department of Justice says that throughout May and June he then supplied the undercover agents with step-by-step plans of how he hoped to attack both the Pentagon and the Capitol building.
If convicted he faces upto 20 years in prison.