JEFFERSON COUNTY — A 33-year-old Mt. Vernon man was sentenced Thursday in Jefferson County court to 50 years in prison after a jury last month found him guilty of two counts predatory criminal sexual assault of a victim under the age of 13.

Jonathan Bieniek was arrested after the Jefferson County Sheriff’s Office secured a warrant for his arrest following an investigation opened in December 2018.

Sheriff’s department investigators were assisted in the investigation by the Illinois Department of Children and Family Services, and employees of the Amy Schultz Child Advocacy Center.

The case was prosecuted by the Jefferson County State’s Attorney’s Office.