Guantanamo Bay Navy Base, Cuba (CNN) The Obama Administration’s first full military trial of a terrorist suspect at Guantanamo Bay Navy Base in Cuba formally started Thursday morning.

The panel of 7 military officers seated for the Military Commission began hearing opening statements in the case against Canadian-born terrorist suspect Omar Khadr, captured on the Afghanistan battlefield in 2002, when he was 15 years old.

The prosecution says Khadr was an enemy combatant in violation of the laws of war, that he was helping assemble and plant roadside bombs for al Qaeda and that he killed a special forces solider, Army Sgt. 1st Class Christopher Speer with a grenade. Speer’s wife, Tabitha, is expected in the courtroom and will be a key prosecution witness in the sentencing phase if Khadr is found guilty.

The defense maintains Khadr was a child solider, coereced by the adults around him and expected to argue that there is no tangible evidence, admist a confusing firefight,  that Khadr three the grenade.

Army Colonel Pat Parrish, the Military Commission judge has predicted the proceedings could take several weeks.

The prosecution Thursday immediately brought in a table-top model to help illustrate what happened on the battlefield and started describing Khadr as a terrorist trained by al Qaeda and "dedicated to killing as many Americans as possible."