(DETROIT) -- The FBI has arrested a Michigan man with an alleged history of threats against its agents in connection to the explosive device that sat for three weeks inside a Detroit federal building.
Matching the bomb components left outside the McNamara Federal building in Detroit to purchases at Home Depot, the FBI zeroed in on Gary John Mikulich, 42, from Iron Mountain, Michigan.
Mikulich was arrested Thursday and charged with explosives violations for allegedly constructing and leaving the device by the federal building on Feb. 26.
The device was moved inside the building by an unsuspecting security guard and sat unattended for three weeks before guards wised up last week.
The incident has prompted numerous questions about security at federal buildings.
The device initially was discovered in a tool bag left outside the federal building on Feb. 26, 2011, but was not scanned or x-rayed by security personnel until last week. The device appears to have contained viable explosives.
Witnesses heard a loud bang and saw smoke with an explosion that sent the metal box containing the bomb 10 feet into the air last Friday when the Detroit police and FBI detonated it.
The FBI used some advanced records checks to identify individuals who had purchased items that were used to construct the device that was placed in a Husky tool bag. According to the FBI affidavit in the case, the Husky brand tool bags are sold exclusively at Home Depot stores.
According to the affidavit, "Representatives from Home Depot confirmed that since October 2010, only nine (9) individuals in the United States have purchased, together at the same time, the following two items: (1) a Husky brand tool bag of the same size as that found at the McNamara Building on February 26, 2011, and (2) a spring wound 60-minute timer by General Electric."
The FBI further determined that of those nine individuals, only one of the purchases was made with cash. The FBI determined this purchase was made in Iron Mountain, Michigan on Feb. 14, 2011. The FBI reviewed surveillance video from the store and determined that it was indeed Mikulich.
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