Updated

GUANTANAMO BAY NAVAL BASE, Cuba (AP) — U.S. military prosecutors offered a plea bargain of five years in prison to a Canadian at Guantanamo who is charged with killing an American soldier in Afghanistan, a newspaper in his home country reported Wednesday.

The Toronto Star, citing anonymous sources, said that 23-year-old Omar Khadr rejected the offer that could have spared him a possible life sentence.

A spokesman for the military commissions, Joe DellaVedova, said he could not confirm the report because the prosecution is prohibited from publicly discussing any possible plea deals. Lawyers for the Toronto-born Khadr told reporters that talks are ongoing but gave no details.

Khadr faces a July military trial on charges that include supporting terrorism and murder. The military says he was an al-Qaida fighter who built roadside bombs in Afghanistan and threw a grenade that killed U.S. Army Sgt. 1st Class Christopher Speer of Albuquerque, New Mexico, during a 2002 battle.

His lawyers deny he threw the grenade and have argued that he deserves leniency because he was 15 at the time of the firefight at an al-Qaida compound.

His defense has asked a military judge to bar the use of incriminating statements he made to interrogators, saying he was mistreated by U.S. authorities while detained in Afghanistan and at Guantanamo. A judge is holding hearings on that request this week at the U.S. base in Cuba.