06/08/2010 12:41 pm ET | Updated May 25, 2011

Stacy Peterson Search Comes Up Empty: Only Animal Bones Found

After days of searching an overgrown field in central Illinois for the body of Stacy Peterson, anthropologists have only discovered animal bones.

Last week, police headed to the field near Peoria after allegedly receiving a tip from former Bolingbrook police officer Drew Peterson's fellow inmate. reported that Drew Peterson told the inmate where he buried Stacy's body, but both the authorities and the Peterson defense team deny that story, pointing out that Peterson has been held in isolation.

NBC Chicago reports that anthropologist Alan Harn, who works for the Illinois State Museum, has only discovered opossum bones thus far, but thinks the use of a magnetometer could help. The device can help investigators find spots where soil has been disturbed.

Harn also stood by the tip about the whereabouts of Peterson's body, and suggested the search continue.

The search is not expected to delay the trial of Drew Peterson, who has been charged in the murder of his third wife, Kathleen Savio. Savio was found drowned in a bathtub in 2004, a death that was initially ruled an accident. But when Stacy Peterson went missing, the Savio investigation was re-opened and ruled a murder. Jury selection in the case is slated to begin July 8.

Prosecutors claim that Peterson murdered Stacy because of what she knew about his previous wife's death, but no body has been found.

Illinois State Police told the Chicago Tribune Monday that "no timetable" has been set to resume the search for Stacy's body, which was halted Saturday night.

Harn, however, said more equipment would allow him to conduct a more thorough search. His digging work in 2005 led to the arrest of serial killer Larry Bright, NBC Chicago reports.

"I'm really not interested so much in the case or the person as I am in trying to get information out of the ground that will tell someone what happened here at this particular site," Harn told the Tribune.

Stacy Peterson has been missing since 2007.