Yemeni defendant Ramzi Binalshibh, who is accused of helping the hijackers enter the United States and of financing the airliner attacks that killed nearly 3,000 people, also claimed that the judge hearing the case was biased.
Binalshibh was initially removed from the latest pre-trial hearing at Guantanamo Bay on that judge's orders, having twice been warned that he would be in contempt of court if he continued to disrupt the proceedings.
"He could not sleep at all last night because of the noise he is exposed to," said Navy Lieutenant Commander Kevin Bogucki. "He is too tired to pay attention."
The latest hearing for the alleged 9/11 plotters, who are eventually expected to go on trial in 2015, was screened for reporters at the Fort Meade military base in Maryland, via a closed-circuit feed.
Also Read
Commander Bogucki said Binalshibh's cell was continually subjected to banging and knocking sounds -- an allegation the US government denies, but which the judge said had not been proven either way.
"I refuse to answer this question as long as the judge is taking a position against me and against my allegations," Binalshibh said, before beginning apparently impromptu claims about US treatment of terror suspects across the globe.
After being warned that it was not his time to speak, the Yemeni suspect, whose alleged crimes include helping the hijackers find flight schools in the United States, cited the words "secret CIA prison" during a muffled speech.
The courtroom camera cut away from Binalshibh while he was being taken out of court, seconds after the judge said he "taken no position" on Binalshibh's allegations.
All five suspects, including the self-proclaimed 9/11 mastermind Khaled Sheikh Mohammed, were present at today's hearing, dressed in traditional white Arab robes and with several of them wearing desert-coloured combat jackets.
Following the lunch recess, Binalshibh returned to the court and was given a second opportunity to acknowledge his rights but he again refused and was removed by guards a second time, amid shouts of "I am not a war criminal".