CHICAGO (WLS) -- Robert Crimo III is facing murder charges after seven people died during a sniper attack at Highland Park's Fourth of July parade. After the mass shooting there were no bombs found along the parade route, even as federal agents searched the landscape. The I-Team has been told by multiple sources, in and out of enforcement, that explosive evidence was found at a family home linked to the accused shooter. That material is in the hands of the FBI.
"This aspect of the investigation is not being handled by the Highland Park Police Department or the Major Crimes Task Force," the Highland Park police chief told the I-Team.
He has referred the I-Team to the FBI, who have refused to comment.
READ MORE: Crimo family had multiple contacts with police before mass shooting
The Tannerite product, legally available online and from many sporting goods stores, was found during a search of a house owned by Crimo's father. The FBI now has possession of the Tannerite explosive material.
An attorney for the father told the I-Team that he would not confirm or deny the Tannerite information but said they are cooperating with authorities.
Buying or possessing Tannerite is not illegal or inappropriate. Police become concerned with its possible misuse, especially in crimes such as the deadly attack that occurred in Highland Park on Independence Day.
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Local and federal agencies say they are continuing to look into the accused shooter's methods, means and motives.
Tannerite falls under the same federal laws as gun powder. It is exempt for sporting use. The company's website lays out numerous safety precautions for using explosive targets, and states that misuse could result in serious injury or death. The company has not responded to messages left by the I-Team.
The FBI would not respond to specific questions for this report but they sent this via email:
Department of Justice policy prevents the FBI from commenting on pending investigations. In all cases, the FBI is dedicated to pursuing every available lead to exhaustively identify new evidence. We encourage any member of the public with information to submit tips at 1-800-CALL-FBI or tips.fbi.gov.