An inquest into the deaths of Sylvia Sheils and Mary Callinan, who were brutally killed at Grangegorman Psychiatric Hospital in 1997, gets underway this morning at the Coroner's Court.
Convicted murderer Mark Nash has never been convicted of the Grangegorman killings despite admitting to them after gardai arrested him for the murder of a young Roscommon couple who were stabbed to death in a frenzied attack.
Nash is currently serving a life sentence for those killings.
Another man, Dean Lyons, who was initially convicted and imprisoned for the Grangegorman murders, was later released but subsequently died.
Nash, who gardai describe as extremely dangerous, has refused to appear at the inquest later today.