A man accused of killing his mother-in-law has been found incompetent to stand trial.

Eugene Pearce, 66, was committed to Utah State Hospital after 3rd District Judge Raymond Uno determined that the defendant is not mentally fit to defend himself against a manslaughter charge.Pearce, a former professional boxer, is charged with punching his mother-in-law, Elizabeth Warren, 86, during a dispute Feb. 4 at 3181 S. 8950 West.

The blow caused Warren to fall backward, striking her head on the floor. She died of bronchial pneumonia due to complications from injuries suffered in the assault.

Pearce stabbed himself following the incident, according to the charges.