A New York City man is facing multiple criminal charges after he allegedly created multiple improvised explosive devices, threw one of them onto a subway track and left others on the rooftops of residential buildings in Manhattan, U.S. prosecutors say.
Michael Gann, 55, was arrested in early June with another explosive device on his person and “before he caused any harm” by detonating any of the devices, NYPD Commissioner Jessica Tisch said in a statement Tuesday.
“That vigilance assuredly prevented a tragedy in New York,” Jay Clayton, the U.S. Attorney for the Southern District of New York, added in a news release outlining the charges on Tuesday.
According to the indictment, Gann ordered three pounds of precursor chemicals online in late May, along with over 200 cardboard tubes and over 50 feet of fuses.
After receiving the materials five days later in Long Island, N.Y., he allegedly mixed the precursor chemicals together and “caused an explosion” when he applied flame to the mixture.
That same day, June 4, Gann then allegedly transported “mixed and unmixed” chemicals and the other materials from Long Island to Manhattan and assembled at least seven IEDs, the indictment says.
Five of the devices were allegedly stored by Gann on the adjoining rooftops of a residential complex in the Soho neighbourhood, along with the remaining precursor chemicals.
He also allegedly stored at least four shotgun shells on the same rooftops, which prosecutors say Gann intended to combine with one or more of the IEDs.
Five improvised explosive devices allegedly manufactured by Michael Gann, 55, are pictured where U.S. prosecutors say they were found on a rooftop in Manhattan on June 5, 2025.
U.S. Department of Justice
One of the explosive devices “contained approximately 30 grams of explosive powder, which is approximately 600 times the legal limit for consumer fireworks,” the indictment reads.
Gann then allegedly threw a sixth IED onto the subway tracks on the Williamsburg Bridge that connects Manhattan to Brooklyn, according to prosecutors.
A red circle indicates what U.S. prosecutors say is an improvised explosive device allegedly manufactured by and thrown onto the subway tracks of the Williamsburg Bridge by Michael Gann in Manhattan on June 4, 2025.
U.S. Department of Justice
One June 5, police arrested Gann near the building where the IEDs were being stored and found a seventh device on his person. Gann allegedly lied to police and said he had disposed of the precursor chemicals and shotgun shells in a dumpster in Chelsea.
Prosecutors say Gann conducted multiple internet searches in May and June leading up to his arrest related to firearms and bomb-making. The searches allegedly included “gun background check test,” “3D gun printing,” “firework chemical equation,” “1/2 stick dynamite” and other related queries.
Before that, on March 27, Gann also allegedly tagged the official U.S. president’s account in a post on the social media platform X that read: “Dear @POTUS, I’m thinking just now here in NYC that it’s too bad that the wall wasn’t built before the National Guard would have to come here for the protests and Riotation (sic) or would you just drop a bomb on this place while and because they seem to be coming and coming?”
The message appears to be a reference to illegal immigration as well as protests against U.S. President Donald Trump’s immigration policies.
Hours before Gann’s arrest on June 5, prosecutors say he posted to his Instagram page, “Who wants me to go out to play like no tomorrow?”
Gann faces charges of attempted destruction of property with explosives, transportation of explosive materials, and unlawful possession of destructive devices. He faces a maximum of 20 years in prison if convicted.
The investigation was carried out by New York’s Joint Terrorism Task Force, which includes members of the FBI, NYPD, and over 50 other federal, state and local agencies.