BILLINGS, Mont. -

 A federal judge has indefinitely delayed a competency hearing for the suspect in a Montana triple-killing who has been unable to stand trial because of mental illness.
    
Sheldon Chase was arrested in October 2011 after his grandmother, cousin and cousin's boyfriend were shot at the family's house on the Crow Indian Reservation near Lodge Grass. His trial has been put off repeatedly for psychiatric evaluations.
    
U.S. District Judge Sam Haddon on Tuesday canceled a Dec. 17 hearing meant to decide if Chase poses a continued risk to the public. No reason was given and Haddon said the hearing date would be reset if appropriate.
    
Government attorneys have said Chase is likely to remain incompetent unless he is forcibly medicated with antipsychotics.