Omar Khadr, Canada's lone detainee in the U.S. naval base at Guantanamo Bay, Cuba, was considered a high risk and kept in custody for his "high intelligence value," according to a new document. (HANDOUT)

Omar Khadr, Canada's lone detainee in the U.S. naval base at Guantanamo Bay, Cuba, was considered a high risk and kept in custody for his "high intelligence value," according to a document released Monday in the latest document dump by whistleblower website WikiLeaks.

The Department of Defense document is marked secret and dated Jan, 24 2004. Khadr was detained after a firefight in July 2002 during which he admitted to throwing the grenade that killed a U.S. Special Forces soldier.

After being held at the maximum security prison base at Guantanamo Bay since Oct. 2002, Khadr pleaded guilty in October 2010 to a series of war crimes, including killing the soldier in the July 2002 firefight. Khadr was sentenced to 40 years, but a plea bargain capped his sentence to eight years. The deal also allows Khadr to return to Canada this fall with support of the U.S. government after serving one year of his sentence at Guantanamo Bay.

The two-page briefing document says Khadr's father is reportedly the fourth in command below Osama bin Laden in al-Qaida.

As of a few days before the document was written, Khadr was assessed as being a member of al-Qaida.

"Based on the detainee's folder, the knowledgeability brief, and subsequent interrogations by JTF (Joint Task Force) Guantanamo, the detainee is of high intelligence value to the United States," reads the report signed by U.S. Army Maj.-Gen. Geoffrey D. Miller.

Detainee poses a high risk, as he is likely to pose a threat to the U.S., its interests or its allies."

The document said that Khadr provided "valuable information" about three training camps at Derunta, Al-Farouq and Khalden, "indicating that the detainee has been to and likely trained at these locations."

Khadr's assessment was one of 779 Guantanamo Bay prisoner dossiers released by WikiLeaks early Monday.