BOSTON - A Massachusetts man was sentenced to 17 years in prison on Thursday for a plot to attack the Pentagon and the U.S. Capitol building in Washington with explosives loaded into remote-control model airplanes.

Rezwan Ferdaus, who was arrested in September 2011 and pleaded guilty in July to terrorism-related charges in a deal with prosecutors, told the court he had devoted a lot of time to self-reflection while in jail awaiting sentencing and that he accepted his fate.

The 26-year-old was arrested after an FBI sting operation in which he requested and took delivery of plastic explosives, three grenades and six assault rifles from undercover FBI agents who he believed were members of the al-Qaida network.

Ferdaus, a Muslim who has a physics degree from Northeastern University, delivered a long, soft-spoken statement in which he offered no apology for his actions but thanked his family and friends for supporting him.

He spoke of "a world filled with injustices," but also said "no dehumanization can serve as justification for inhumanity in other places."

The 17-year sentence, which also includes 10 years of supervised release, was the result of a July plea agreement worked out between his attorneys and prosecutors.

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Ferdaus pleaded guilty to charges of attempting to destroy and damage a federal building and attempting to provide material support to terrorists. Prosecutors dropped four other counts that could have raised the total possible sentence to 35 years.

Before approving the sentence, Stearns told Ferdaus that he was impressed by his self-reflection.

USAMA via AFP - Getty Images

A remote-control model of a 1950s U.S. Navy Sabre jet fighter that prosecutors said belonged to Rezwan Ferdaus is seen in this undated photo released by the United States Attorney's Office District of Massachusetts.

"You don't need any lecture from me. Your statement convinces me that you have the character and the capacity to search your own soul," Stearns said. "I'm going to leave it to you to finish that journey."

Parents: Depression led to mental illness
In a letter to Judge Richard Stearns, Ferdaus' parents, Showket and Anamaria Ferdaus, said he slipped into a depression during his senior year at Northeastern, which led to mental illness that was "obviously visible" to his family since late 2009.

They said they tried to get him to see a doctor but he would not.

"We took a very cautious approach. After all, he was over 18 and we could not force him to see a doctor. That is the American way. We felt helpless," they wrote in their letter.

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Ferdaus' attorney, Miriam Conrad, told reporters after the hearing that her client had shown no interest in terrorism before FBI investigators approached him.

"There was no evidence ever produced that Mr. Ferdaus sought out contact with any outside groups before the government became involved or even after the government became involved," Conrad said.

'Wanted to become a terrorist'
Assistant U.S. Attorney Jack Pirozzolo disagreed.

"He was a person who decided that he wanted to become a terrorist," Pirozzolo said, adding that before the FBI investigation began, Ferdaus had tried to obtain weapons illegally from an area gun shop and performed surveillance on a train station in his hometown of Ashland, Massachusetts.

"Those events predated the undercover operation that unfolded here," Pirozzolo said.

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Ferdaus planned to carry out the attacks on the Pentagon, located in Arlington, Virginia, and the Capitol using a scale model of a U.S. Navy F-86 Saber fighter jet about the size of a picnic table, which he kept in a storage locker in suburban Boston, authorities said.

Authorities said the public was never in danger from the explosives, which they said were always under the control of federal officials.

The government had alleged that Ferdaus told undercover agents of his plans to commit acts of violence against the United States by "decapitating" its "military center" and killing "kafirs," an Arabic term meaning non-believers.

Reuters and The Associated Press contributed to this report.

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Reuters / U.S. Department of Justice / Handout

Rezwan Ferdaus, a Massachusetts man who allegedly plotted to fly explosives-packed model planes into the Pentagon and U.S. Capitol, has reignited concern about the risk of a home-grown militant attack in the United States.

BOSTON, Mass. -- The Massachusetts man charged with plotting to attack the Pentagon and the U.S. Capitol with remote-controlled model airplanes filled with explosives entered a guilty plea in a Boston federal court on Friday.

Rezwan Ferdaus told a packed courtroom, including his distraught family members, that he would accept the plea deal for a 17-year prison term that was hammered out by his attorneys and prosecutors this month.

Ferdaus' mother sobbed as her son was led away by U.S. Marshals at the end of the hearing.

The charges against Ferdaus had carried a potential combined sentence of 35 years in prison. Sentencing will take place on November 1.

Ferdaus, 26, of Ashland, Massachusetts, pled guilty to attempting to destroy and damage a federal building, and attempting to provide material support to terrorists.

Reuters / U.S. Department of Justice / Handout

A scale model of a U.S. Navy F-86 Sabre fighter plane in photo released by the U.S. Justice Department after being submitted to U.S. District Court in Massachusetts as part of a criminal complaint and affidavit filed by the Federal Bureau of Investigation in Boston, September 28, 2011.

He initially pleaded not guilty to a total of six charges after his arrest in September 2011. Authorities dropped four charges in exchange for the guilty plea.

After entering his guilty plea, Ferdaus tried to lean over to comfort his crying mother but was quickly pulled away by U.S. Marshals. She sobbed uncontrollably and had to be supported by family members as her son was led out of the courtroom.

Ferdaus was arrested after an FBI investigation during which he requested and took delivery of plastic explosives, three grenades and six assault rifles from undercover FBI agents that he believed were members of al-Qaida.

At the time of his arrest, the physics graduate from Boston's Northeastern University had obtained one remote-controlled aircraft, a scale model of a U.S. Navy F-86 Sabre fighter jet about the size of a picnic table.

He kept the model in a storage locker in suburban Boston rented under the name "Dave Winfield."

Plan to 'decapitate' U.S. military center
Authorities said the public was never in danger from the explosives and weaponry, which they said were always under the control of federal officials during the sting operation.

The government had alleged that Ferdaus told undercover agents of his plans to commit acts of violence against the United States by "decapitating" its "military center" and killing "kafirs," an Arabic term meaning non-believers.

Prosecutors said Ferdaus began planning jihad, or holy war, against the United States in 2010 after becoming convinced through jihadi websites and videos that America was evil. He later contacted a federal informant and began meeting to discuss the plot with undercover agents.

Counterterrorism experts and model-aircraft enthusiasts say it would be nearly impossible to inflict large-scale damage using model planes.

But both inside and outside court Friday, prosecutors described an elaborate plan they said Ferdaus was committed to carrying out.

Assistant District Attorney Stephanie Siegmann said that if the case had gone to trial, prosecutors would have used recordings on which Ferdaus is heard detailing the plot.

Siegmann said there were two main parts of his plan: to blow up the Pentagon and U.S. Capitol using remote-controlled planes and to kill American soldiers in Iraq and Afghanistan using improvised explosive devices detonated by modified cellphones.

The planes, measuring 60 to 80 inches in length and capable of speeds greater than 100 mph, would be guided by GPS and packed with 5 pounds each of plastic explosives.

Siegmann said Ferdaus traveled to Washington, D.C., to scout out his targets and later gave the undercover agents surveillance photos and maps. She said Ferdaus told them his plan "ought to terrorize" and "ought to result in the downfall of this entire disgusting place."

Siegmann said Ferdaus modified 12 cellphones so they could act as an electrical switch for an IED.

After giving the first device to the undercover agents, the agents lied and told him it had been used in Iraq and killed three U.S. soldiers.

Siegmann said Ferdaus was "visibly excited" to learn his device had been used successfully and said, "That was exactly what I wanted."

Ferdaus told Judge Richard Stearns that he was being treated for mild depression and anxiety before he was arrested and is now taking anti-anxiety medication.

During an earlier court hearing, Ferdaus' lawyers suggested that the FBI ignored signs of mental illness in Ferdaus while investigating him. An FBI agent acknowledged that the FBI had received reports about bizarre behavior by Ferdaus, including a report to Hopkinton police about one incident in which authorities say he stood in the road not moving and appeared to have wet his pants.

When asked Friday whether Ferdaus' mental health was taken into account when making the 17-year sentencing recommendation, First Assistant U.S. Attorney Jack Pirozzolo cited Ferdaus' composed responses to the judge's questions and the judge's comment that Ferdaus is "obviously an intelligent and well-educated young man."

"He answered clearly; he was lucid," Pirozzolo said.

Siegmann said the defense didn't request a mental examination. 

Ferdaus is a Muslim born and raised in Massachusetts to parents of Bangladeshi descent.

Reuters and The Associated Press contributed to this report.

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