A 29-year-old Detroit man was arrested by the FBI after allegedly attempting to buy grenades in addition to amassing a large arsenal of weapons, ammunition, tactical gear and training material “unlikely” to be used recreationally, according to a criminal complaint filed Monday.
Sebastian Gregerson, also identified by the FBI as Abdurrahman Bin Mikaayl, was arrested on Sunday and charged with unregistered possession of a destructive device and the unlicensed receipt of explosive materials. The charges follow a 16-month investigation by the FBI, which was initiated after a confidential source “alerted the FBI that Gregerson claimed to have in his possession both grenades and bazookas,” according to court documents.
The criminal complaint did not allege a motive for attempting to procure illegal explosives, but Gregerson described at one point to the undercover FBI employee “his plans for a full tactical response to law enforcement if they came for him, including the use of grenades,” according to court documents.
Gregerson is due back in court for a detention hearing on Thursday. A message left with Gregerson’s attorney was not immediately returned Tuesday.
According to the affidavit, Gregerson, over a period of eight months, had purchased 700 rounds of ammunition for an AK-47, tactical gear and clothing, videos used by military and law enforcement for tactical firearms techniques, military-grade splints for medical care, commercial-grade road spikes and other hardware typically used for combat training.
The affidavit reveals the FBI began physical surveillance of Gregerson as early as January and mentions multiple accounts of a “court-authorized method of tracking Gregerson’s location,” where he visited sporting goods stores shopping for firearms, eventually purchasing a Kel-Tec Sub 200 9mm, a “long-barreled firearm” and a handgun from a man at a gas station parking lot.
Eventually, the FBI utilized an undercover employee to record conversations between Gregerson and himself in which Gregerson allegedly expressed his desire to obtain explosives. The undercover FBI employee stated to Gregerson that he had a contact who could possibly procure the explosives and introduced an FBI colleague to act as a weapons dealer who was able to obtain grenades.
Gregerson allegedly struck a deal with the undercover FBI employee for five M67 fragmentation grenades in exchange for his Beretta M9 handgun as payment. As soon as the grenades were handed to Gregerson, he was arrested.