BILLINGS, Mont. -

Attorneys a for a Colorado man charged with killing an eastern Montana teacher are asking a judge to declare the defendant incompetent to stand trial.
    
The attorneys for 24-year-old Michael Keith Spell on Thursday filed a request with District Judge Richard Simonton in Sidney to hold a competency hearing for their client in mid-March. They want the criminal proceedings against Spell suspended and for him to be institutionalized because of mental disabilities.
    
Prosecutors say the Parachute, Colo., man strangled or asphyxiated 43-year-old Sidney High School teacher Sherry Arnold when he attempted to abduct her as she was jogging on Jan. 7, 2012.
    
Spell was returned to the Richland County jail last week after a two-month competency evaluation at the Montana State Hospital in Warm Springs. The results have not been released.