The FBI arrested a notorious white supremacist livestreamer in an early morning raid in Florida on Tuesday.

FBI agents, working with Fort Lauderdale police and the FBI’s Joint Terrorism Task Force, arrested Paul N. Miller, 32, on one charge of being a “convicted felon in possession of a firearm.” The FBI said in a press release that Miller was arrested without incident.

Miller’s neighbors in Fort Lauderdale’s Riverside neighborhood reported hearing flashbangs during the raid, which took place around 5 a.m. ET, local TV station NBC 6 reported. One neighbor described seeing law enforcement officers carrying out a box that appeared to have “a shotgun on the front or an AK.”

Miller, who goes by the name “Gypsy Crusader” online, has amassed more than 40,000 followers on Telegram, a messaging app and social media network popular with far-right extremists. Many of Miller’s videos feature him dressing up as characters like the Joker or Nintendo’s Mario, then hurling racial abuse at strangers, including children, through the randomized chat app Omegle. Miller can be seen holding a gun in some of his videos.

A grand jury indicted Miller on the firearms charge on Feb. 25, according to court records unsealed Tuesday. Miller is charged with illegally possessing a gun on Jan. 17, 2018. The indictment doesn’t describe the 2018 incident in which Miller allegedly had the firearm.

Miller’s Tuesday arrest sent shockwaves through internet extremist circles. Miller had recently sold patches promoting his channel to his supporters, with his arrest raising fears among other extremists that the FBI could access his customer files and find out their own names and addresses.

In messages captured by extremism researcher Hilary Sargent, Miller’s supporters worried about the possibility that they could soon become FBI targets themselves.

If convicted, Miller faces up to 10 years in prison on the gun charge.