ST. CHARLES, Ill. (AP) — A former suburban Chicago man has been sentenced to life in prison for sexually assaulting two children he knew and who were under 13 at the time.

A Monday statement from the Kane County state’s attorney’s office says 33-year-old Timothy M. Arnold assaulted the children over six years in Aurora, starting in 2011.

Arnold had lived in Aurora. More recently, he resided in Lawrenceburg, Tennessee.

Jurors convicted him in January of eight counts of predatory criminal sexual assault of a child and five counts of aggravated criminal sexual abuse.

Prosecutors say the life sentence was mandatory because Arnold sexually assaulted several children under the age 13 when he was older than 18. A judge formally imposed the mandatory sentence Friday.

Monday’s statement didn’t say how Arnold knew the victims.