The family of a former University of Manitoba student convicted of aiding a terror plot in Afghanistan has written to a U.S. court pleading for leniency ahead of his sentencing on March 7.

A jury convicted Muhanad Al Farekh in a New York court last September of providing support to terrorists and other charges related to a 2009 explosion at a U.S. military base in Afghanistan.

The minimum sentence is seven years, but the U.S. government is asking the court to impose the maximum penalty of life in prison.

"I have known Muhanad for the entirety of his life, he is a wonderful person, loving, caring, kind," his grandmother wrote to Federal District Court Judge Brian Cogan.

The grandmother, who lives in Winnipeg, wrote that her grandson was an active volunteer in the community, has a "good heart inside" and "continues to have unwavering support from his family."

Letters from family members in support of Al Farekh were filed in the New York court this week.

In this video filed in court, Al Farekh is seen in a Winnipeg apartment watching a video that was published by the Islamic Army in Iraq. 1:15

Al Farekh, 32, had moved to Winnipeg in 2003 to live with his grandmother and uncle in preparation for his university education.

Convicted on 9 charges

He and two other University of Manitoba students, Ferid Imam and Maiwand Yar, left Winnipeg for Pakistan in March 2007. Court heard evidence that they went to join al-Qaeda.

In the months before their departure, court was told, the three men watched video recordings encouraging violent jihad, listened to jihadist lectures and talked about their support for violent Islamist extremism.

While Imam and Yar seemed to have disappeared, the Texas-born Al Farekh resurfaced. U.S. authorities say he climbed to a high-ranking position in the al-Qaeda operation.

Before Al Farekh was captured, the U.S. administration debated whether to kill him in a drone attack in Pakistan, according to a 2015 New York Times report, which would have been a rare and controversial move against an American citizen.

Al Farekh was arrested in Pakistan in 2014 and transferred to the custody of U.S. authorities, who took him to New York in April 2015 to face trial.

He was convicted on all nine charges — which included providing support to terrorists, conspiracy to bomb a government facility and use of explosives — in connection with an attack on an American military base in Afghanistan.

Bomb would have been 'catastrophic'

On Jan. 19, 2009, two vehicles loaded with explosives lumbered toward Forward Operating Base Chapman in Afghanistan's Khost province where, court heard, some 90 Americans were working.

The first driver detonated his load outside the gates and died in the explosion.

Court video showing the aftermath of the January 2009 attack on a U.S. military base in Afghanistan. 0:35

The second truck became lodged in the crater from that explosion and did not detonate. That driver was shot dead as he tried to escape. Technicians dismantled the bomb and gathered evidence from it.

The second bomb was much bigger — 3,400 kilograms — and court heard evidence it would have had a "catastrophic" effect, killing many people, if it had entered the base and exploded as planned.

One American soldier was injured in the attack, along with several Afghan citizens, including a pregnant woman who got a piece of shrapnel lodged in her back.

Armed with fingerprint evidence from the packing tape used on the bombs, the prosecution tied Al Farekh to the plot. The jury heard there were 18 prints that were a match to Al Farekh, but the defence lawyer argued the fingerprint evidence involved "guesswork."

Defence seeks 'hope and a future'

The defence told court Al Farekh was "an innocent man falsely accused" of crimes he didn't commit.

In its submission to the court on sentencing, defence lawyers argued none of the offences Al Farekh was convicted of call for penalties beyond seven years.

They said the sentence should be "sufficient but not greater than necessary," and that a sentence of lifetime incarceration for the 32-year-old who has no criminal history would be "far greater than necessary."

"We urge the court to impose a sentence that leaves this individual human being with hope and a future and a chance to reunite with his large and loving extended family," said the defence sentencing memorandum filed this week.

The memorandum noted that although there were injuries from the attack in Afghanistan, there were no deaths.

The submission noted Al Farekh has been held in solitary confinement for nearly three years.

'More than what the jury concluded'

Al Farekh has submitted to the court "that he does not believe in violence for any purpose, including religion-based violence."

"Mr. Al Farekh is more than what the jury concluded from the evidence," the defence submission said.

This FBI video recreation entered into evidence shows an explosion with just one fifth of the force of the bomb that failed to go off outside Forward Operating Base Chapman in January of 2009. 0:43

"He is also a brother, a son, a grandson, a nephew and a friend. As the many letters submitted on his behalf attest, he is a person with love of knowledge and learning who is also loving, generous, kind, funny, and loved by many people. He has never been known to be violent. He has a life ahead of him and people to care for him when released from confinement."

In his letter to the judge, Al Farekh's father, Mahmoud Al Farekh, wrote that he believed his son travelled to Pakistan in 2007 to go to university. He revealed that he met him there and that they toured the campus and met with an admissions officer.

Al Farekh's mother wrote a letter referring to her son's period of incarceration. "I was given the chance to see my son only once and the thought of the kind of suffering my son must be going through in his solitary confinement is unbearably painful."

Uncle calls him 'a fun person'

Al Farekh's uncle wrote to the judge, "Muhanad is a fun person, loves life and is full of it, who always kept a grin that made him shine." He said Muhanad is "an amazing person, sincere and kind."

The prosecution argued, "The sentence imposed should send a message to all would-be terrorists that if they conspire to train and fight, and if they support al-Qaeda's call to murder Americans, they will be caught, prosecuted, and then imprisoned for life."

Prosecutors pointed to seven cases in which conviction on similar charges in U.S. courts resulted in life sentences.

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