FACTBOX: Pentagon probe warned on Qahtani treatment in 2005

(Reuters) - Three years before a senior Pentagon official concluded that Mohammed al-Qahtani was tortured at Guantanamo Bay, military investigators warned that his treatment in U.S. custody was abusive and degrading.

Qahtani, a Saudi national accused of being the 20th hijacker in the September 11 attacks, had proved impervious to standard military interrogation in 2002 when former Defense Secretary Donald Rumsfeld authorized special methods to break his will.

Two U.S. generals who investigated the case -- Randall Schmidt and John Furlow -- said in July 2005 that most of the techniques used on Qahtani were "legally permissible under the existing guidance" and did not "rise to the level of prohibited inhumane treatment." But they warned that the intense application of the methods resulted in "the cumulative effect being degrading and abusive treatment."

Qahtani, who had to be treated for heart problems twice, in late 2002 and early 2003, attempted suicide just before Susan Crawford, who oversees the U.S. war court in Guantanamo Bay, dismissed charges against him last May.

Crawford was quoted in the Washington Post on Wednesday as saying she dismissed the case after concluding that his treatment met the legal definition of torture and impacted his health. He remains in custody.

Following are interrogation techniques used against Qahtani, according to the Schmidt-Furlow report.

The report said his interrogators:

* used air conditioning to make his living conditions uncomfortable, twice reducing his body temperature to 92-97 degrees Fahrenheit (33 to 36 degrees celsius);

* Conducted 48 days of 20-hour interrogations during a 54-day period;