CHICAGO (CBS) — A former Aurora man agreed to a 16-year prison sentence in exchange for a guilty plea to four counts of criminal sexual assault, according to the Kane County State’s Attorney’s Office.

Martin Beyer, 53, plead guilty to assaulting four children he knew over a 12-year period.

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53-year-old Martin L. Beyer today agreed to a sentence of 16 years in the Illinois Department of Corrections in exchange for a guilty plea to criminal sexual assault, Class 2 felony, 4 counts. (Kane County State’s Attorney)

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According to Kane County Assistant State’s Attorney Lori Schmidt, Beyer sexually assaulted four children, younger than 18-years-old, between 2001 and 2013.

Beyer must register for life as a sexual offender. He had been freed on $30,000 bond, but bond was revoked upon his conviction.

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“This defendant had been sexually abusing children for more than a decade before he was caught. He was stopped because one of his victims came forward and disclosed his criminal behavior. This brave disclosure prompted additional victims to bravely come forward and expose more of the defendant’s abuse. These victims should be proud of their strength and courage. I comment the work of Assistant State’s Attorneys Lori Schmidt and Sarah Seberger, the Kane County Child Advocacy Center, and the Aurora Police Department,” said Kane County Assistant State’s Attorney William Engerman, chief of the office’s Criminal Trials Bureau.