FARMINGTON A Sunset man pleaded guilty and mentally ill Tuesday in 2nd District Court to one count of aggravated sexual abuse of a child in return for having a second similar charge dismissed.

Michael D. Thornock, 39, 1009 N. 250 West, pleaded guilty to the first-degree felony, which carries a prison term of 5-years to life and a minimum mandatory sentence of 3, 6, or 9 years.Judge Rodney S. Page ordered an Adult Probation and Parole pre-sentence report and directed that Thornock be transferred to the Utah State Hospital for a mental evaluation before a June 24 sentencing.

It will be Thornock's second evaluation at the state facility. Defense attorney Stephen Oda requested one at Thornock's Jan. 20 arraignment to determine if he understood the charges against him and was capable of participating in his defense.

Based on the hospital's findings, Page determined Thornock is competent and set a trial date.

At his pretrial hearing Tuesday, Thornock signed an affidavit containing one charge of aggravated sexual abuse, admitting to abusing an 8-year-old girl between 10 and 12 times last summer in his Sunset home.

He also admits in the affidavit to a 1984 conviction of attempted forcible sexual abuse of a child, a third-degree felony.