July 10, 2012  -- A Massachusetts man accused of plotting to attack the Pentagon and U.S. Capitol building with model planes filled with C-4 explosives will plead guilty to two terror charges, say prosecutors, and serve a 17-year federal sentence.

According to court documents filed by prosecutors and attorneys for Rezwan Ferdaus, a Northeastern University physics graduate and U.S. citizen, Ferdaus has agreed to plead guilty to attempting to provide material support to terrorists and attempting to damage and destroy federal buildings by means of an explosive.

Ferdaus, 27, was arrested at the culmination of a long-term sting operation by undercover FBI agents posing as Al Qaeda operatives.

According to investigators, Ferdaus believed he had been working for al Qaeda since 2010, when he began modifying cell phones to serve as electrical switches for improvised explosive devices (IEDs) to be passed on to fighters in the Middle East and then providing them to the supposed operatives.

"During a June 2011 meeting, he appeared gratified when he was told that his first phone detonation device had killed three U.S. soldiers and injured four or five others in Iraq. Ferdaus responded, 'That was exactly what I wanted,'" the Department of Justice said in a statement in September 2011.

The alleged model-plane plot called for Ferdaus to command a team of six operatives to use remote-controlled aircraft filled with explosives to attack the Pentagon and the Capitol before shooting survivors in a subsequent "ground" attack.

Ferdaus allegedly travelled to Washington, D.C. to conduct reconnaissance on his targets. Ferdaus was arrested in Framingham, Mass. in September 2011 after he took delivery of the AK-47 rifles, grenades and C-4 explosives that were allegedly to be used in the attack.

Federal officials say the public never faced any danger during the sting, because the "explosives" furnished to Ferdaus by undercover officers were inert. The Justice Department says agents gave Ferdaus every opportunity to back out of the plot, but he refused even after being warned that his attacks could kill women and children.

Ferdaus told undercover officers that he had been radicalized on the internet.

As part of his plea deal, prosecutors and Ferdaus have agreed to a 17-year sentence.

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