Robert Snell

The Detroit News

Detroit — A Detroit man accused of plotting jihad on behalf of the Islamic State accepted a plea deal with federal prosecutors Thursday and could spend up to five years in prison.

Sebastian Gregerson admitted he acquired a fragmentation grenade last summer from an undercover FBI employee, a crime because the grenade was an unregistered destructive device.

“I am guilty of that count,” Gregerson, 30, told U.S. District Judge Arthur Tarnow.

The charge is a 10-year felony, but Gregerson could spend half as much time in federal prison under terms of the plea deal. Tarnow will sentence Gregerson, aka Abdurrahman Bin Mikaayl, June 30.

In court filings, prosecutors allege Gregerson acquired the grenades and other weapons in preparation for an attack in support of the Islamic State.

Gregerson’s sentencing guideline range is 37-46 months in federal prison and the plea deal caps the potential sentence at 60 months. The guidelines are advisory and Tarnow can go above or below the range.

Under the plea deal, Gregerson also could be sentenced to three years of supervised release – the federal version of parole. And his computer and internet access would be restricted for three years.

Gregerson, wearing handcuffs and ankle chains and dressed in a khaki prison uniform, was stoic during the plea hearing but smiled at his wife and father, who sat in the courtroom gallery.

His father waved away reporters who approached for comment.

The plea nearly brings to a close a high-profile terror case that spanned at least three states but leaves several unanswered questions.

The FBI believes Gregerson was plotting violent jihad with a radical former imam and was part of a broader-based group of like-minded supporters in Maryland, according to court records and prosecutors.

Gregerson converted to Islam after high school and worked as an hourly Target employee. He amassed an armory of weapons that were purchased, in part, by the former Maryland imam, Suleiman Bengharsa, according to sealed federal court records obtained by The Detroit News.

The armory also included AK-47s, handguns, rifles, a shotgun and thousands of rounds of ammunition.

Bengharsa has not been charged with a crime and told The News that he does not support the Islamic State.

The status of the investigation into Bengharsa was unclear Thursday.

Separately, Gregerson was indicted Dec. 14 in a Virginia federal court and accused of conspiring to illegally purchase firearms through a straw buyer.

He is expected to plead guilty to a charge in that case, which will be transferred to federal court in Detroit, his lawyer David Tholen said.

The plea hearing Thursday was scheduled eight months after Gregerson was arrested in Monroe after allegedly buying fragmentation grenades from an undercover FBI agent.

Gregerson arrived with a handgun that he planned on trading for five fragmentation grenades, court records show.

The undercover agent took the gun and gave the grenades to Gregerson. The grenades contained several ounces of TNT and another explosive similar to the type used by underwear bomber Umar Farouk Abdulmutallab in the failed Christmas Day 2009 terror attack aboard a Detroit-bound airliner.

rsnell@detnews.com

(313) 222-2486

Twitter: @robertsnellnews