The claim was made by Colonel Karen Mayberry, chief defence counsel, at a preliminary hearing at the US military prison in Guantanamo Bay. She also said that 'hundreds of thousands' of files went missing from a computer network through which the defence lawyers communicated with each other, according to The Sun Daily. The defence are seeking to have the proceedings frozen as a result of these alleged violations.The five men face the death penalty if they are convicted of involvement in the attacks on 11 September 2001.