GUANTANAMO BAY, Cuba – The latest – and seventh – judge presiding over the Sept. 11, 2001 hearings at the Guantanamo Bay Naval Base in Cuba said he feels "zero pressure" to conclude the case nearly 20 years after the terror attacks took place.

Khalid Sheikh Mohammed, the accused mastermind behind 9/11, and four other Gitmo detainees appeared in court Tuesday for the first time in 500 days for pretrial headings, after delays brought on by the coronavirus pandemic. 

The hearings, which resumed Wednesday, are the latest attempt to advance a case that has been bogged down for years amid legal challenges

Air Force Lt. Col. Matthew McCall, the latest judge on the case, said Wednesday in the courtroom that the death penalty is a "valid option" for the five accused 9/11 planners and said he "can be impartial" and "pretty open-minded."

Air Force Lt. Col. Matthew McCall is presiding over the Sept. 11, 2001, case at Guantanamo Bay. (Credit: Office of Military Commissions)

Air Force Lt. Col. Matthew McCall is presiding over the Sept. 11, 2001, case at Guantanamo Bay. (Credit: Office of Military Commissions)

McCall said Wednesday morning while taking questions from detainee's lawyers that he is under "zero pressure to get this case done" and "rush" a trial that has not been scheduled yet as the families of 9/11 victims await a verdict for those involved in planning the attacks that killed their loved ones in 2001.

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The Air Force member has faced some skepticism for only having two years of experience as a judge and answered several questions Wednesday about his familiarity with Islam, with the torture detainees underwent at clandestine CIA prisons before they were sent to Gitmo and with the case in general.

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McCall spent five years as a defense attorney and did a tour in Iraq as a prosecutor with Task Force 134 in Baghdad in 2004. He also helped put away nearly 100 suspected terrorists, he said.

** FILE ** Khalid Shaikh Mohammed, the alleged Sept. 11 mastermind, is seen shortly after his capture during a raid in Pakistan Saturday March 1, 2003 in this photo obtained by the Associated Press. American authorities investigating the killing of Wall Street Journal reporter Daniel Pearl in Pakistan now believe that he was slain by the hand of Mohammed. The U.S. acknowledgment of Mohammeds suspected role was first reported in the Wall Street Journal Tuesday, Oct. 21, 2003. (AP Photo)

Khalid Shaikh Mohammed, the alleged Sept. 11 mastermind, is seen shortly after his capture during a raid in Pakistan Saturday March 1, 2003 in this photo obtained by the Associated Press. (AP Photo)

The judge, who described himself as a Christian who "doesn’t go to church very often," said he has read authors Bernard Lewis and Thomas Friedman was Cheryl Bormann, attorney for detainee Walid bin Attash, asked him about his familiarity with Islam. Bormann appeared to take umbrage with the judge reading Bernard Lewis. 

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Pretrial hearings will resume Friday morning. 

Mohammed and his four other co-defendants are charged with several crimes, including terrorism, hijacking and 2,976 counts of murder for their alleged roles in planning and providing logistical support to the Sept. 11 plot. 

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The quintet has been held at Guantanamo Bay since September 2006 after several years in secret CIA detention facilities following their capture.

Fox News' Vandana Rambaran contributed to this report, as well as The Associated Press.