A US military lawyer is accusing the Pentagon of a massive cover-up in an investigation that cleared soldiers of abusing the Guantanamo detainee David Hicks. Hicks is an Australian citizen who was captured in Afghanistan over four years ago. His attorney, Major Michael Mori, says investigators ignored evidence including corroborating testimony from four Guantanamo prisoners. Hicks has alleged he was regularly beaten by guards at the prison and by US soldiers in Afghanistan.