text: The week-long pre-trial hearing at Guantanamo Bay will largely focus on issues of secrecy.
  Khalid Sheikh Mohammed is accused of masterminding the attacks while the others are implicated for providing support for the co-ordinated hijacking.
  In May, a chaotic hearing in the case lasted 13 hours.
  During that hearing, which formally charged the five men, the defendants made defiant outbursts and refused to answer the judge's questions or use the translation system.
  In addition to Khalid Sheikh Mohammed, defendants Ramzi Binalshibh, Mustafa Ahmad al-Hawsawi, Ali Abd al-Aziz Ali and Waleed bin Attash are being prosecuted in a special military tribunal for wartime offences known as a military commission.
  They are charged with conspiring with al-Qaeda, terrorism, and one count of murder for each known victim of the 11 September attacks at the time the charges were filed - 2,976 in total.
  The five face a possible death penalty sentence if convicted.
  CIA waterboarding tapes revealed
  On Monday, the defendants listened calmly and answered the judge's questions, although Khalid Sheikh Mohammed said: "I don't think there's any justice in this court."
  Defence lawyers argued during the hearing that their clients should not be forced to attend the rest of the week's hearings, because the forcible transport from their high-security cells may remind them of their time at secret CIA prisons.
  Before their transfer to the US base at Guantanamo Bay in 2006, the defendants were held for years in secret CIA prisons.
  All five have said they were tortured during interrogations. Khalid Sheikh Mohammed was repeatedly water-boarded before being brought to Guantanamo.
  "We have to talk about torture," Air Force Captain Michael Schwartz, a defence lawyer, said on Monday.
  But Judge James Pohl said the issue was not relevant at this stage.
  Prosecution lawyers have said the use of waterboarding and similar methods could be relevant when determining whether prisoners' statements were voluntarily given.
  The court is also expected to hear a defence request to abolish what they term a "presumptive classification" that treats any discussion of the CIA prisons as top secret, as well as a media request to limit closing of the courtroom for secret sessions.
  Judge Pohl ultimately ruled that the defendants would not be forced to attend hearings scheduled to run through the end of this week, but did not rule out further pre-trial hearings.
  He said all would have to be present for their trial, which is not likely to start for more than a year.
target: Khalid Sheikh Mohammed and four others accused over the 9/11 attacks have appeared at a US military tribunal for the first time in five months.