CHICAGO (WLS) -- Nearly eight months after the Independence Day parade shooting, there is new information about the plot that claimed seven lives in Highland Park.
Investigators say accused mass killer, Robert Crimo III, had his sights set on many more casualties.
The intelligence pieced together by police and federal agents reveals a trail of do-it-yourself explosives and other weaponry that could have expanded the carnage beyond what was done with an assault rifle from a rooftop.
Authorities revealed little evidence after charging Crimo. However, now, we have the backbone of the plot that investigators have tracked down and they say Crimo has confessed to.
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Newly released federal court records show the attack plot had been in the works not just for months, but for years.
That detail is among new elements of the case revealed in search warrant paperwork previously sealed by a judge in Chicago.
The six warrants paint a much more complete picture of an elaborate scheme by Crimo, who federal agents say told them he wanted to "wake people up" in America.
His plan, according to the court records, involved homemade bombs, milk cartons laden with large bullets, an electronic remote detonator powered by a buffet of batteries, circuit boxes, electrical wiring and switches.
The arsenal of explosives were so heavy that Crimo couldn't even carry them to the parade, according to what he told federal agents. They say Crimo said he left them behind for possible later use. Instead, he used a rifle from a rooftop on the parade route.
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Crimo told agents that he concocted battle gear and kept it hidden under lock and key, so family members wouldn't get hurt.
As the I-Team first reported last July, shortly after the rampage, Crimo had stockpiled a supply of Tannerite explosive material, some of which is pictured in the newly unsealed search warrant records.