FBI and Illinois State Police officials on Monday were searching a forest preserve in Shorewood as part of an "ongoing criminal investigation."
Officials declined to elaborate on the search at the Hammel Woods near Interstate 55 and Black Road, but two major missing persons cases remain open in Will County: Stacy Peterson and Lisa Stebic.
Lisa Stebic was last seen the weekend of April 30, 2007, at her house in Plainfield. Her husband, Craig Stebic, told police he was working in the backyard and their kids had walked to the store to buy candy when Stebic left to go work out.
The pair were in the midst of a bitter divorce at the time of Lisa Stebic's disappearance.
Stacy Peterson vanished six months after Stebic. She's the fourth wife of Drew Peterson, who was convicted in September of killing his third wife, Kathleen Savio.
In the months after Stacy Peterson disappeared, the FBI joined with local agencies in a number of unsuccessful searches in and around the Bolingbrook area.
In 2009, Drew Peterson's step-brother, Thomas Morphey, told a national television audience that he was convinced Peterson killed Stacy, and he said he helped the former Bolingbrook police sergeant move a blue barrel from his Bolingbrook home to an SUV.
Morphey said he believes Stacy Peterson's body was inside that barrel. It has never been recovered.
Drew Peterson maintains Stacy is still alive and left him for another man.