Additional charge for Michigan man in counterterrorism probe

(Reuters) - A Michigan man arrested earlier this year in a federal counterterrorism probe has been indicted on a new charge of receiving explosive materials with the intent to harm or kill, according to court documents.

Sebastian Gregerson, a Detroit resident who also goes by the name Abdurrahman Bin Mikaayl, was charged on Thursday, according the indictment against him filed with the United States District Court in Michigan.

Gregerson previously was charged with unregistered possession of a destructive device and the unlicensed receipt of explosive materials.

An attorney for Gregerson was not immediately available for comment.

Gregerson was arrested by the Federal Bureau of Investigation's counterterrorism squad in August on suspicion of illegally purchasing an arsenal of explosives and other devices capable of mass casualties.

The FBI arrested Gregerson, 29 at the time, when he met with undercover agents at a gas station and traded a Beretta M9 handgun as payment for several grenades, according to a criminal complaint. He was not licensed to receive explosive materials.

The agency began its probe in April 2015 when an anonymous informant alerted the agency that Gregerson said he was in possession of grenades and bazookas, the complaint said.

U.S. authorities also found an apparent link between Gregerson and the radical U.S.-born al Qaeda recruiter Anwar al-Awlaki, local media said.

Details behind the new charge were not disclosed in the indictment.

(Reporting by Laila Kearney; Editing by Marguerita Choy)