GREEN TOWNSHIP, Ohio — A Green Township man is in federal custody, accused of detonating three homemade explosive devices in Butler and Hamilton counties earlier this year, according to Acting U.S. Attorney Kelly Norris.
The FBI Joint Terrorism Task Force arrested 50-year-old Robert Gilb on Tuesday, the FBI said.
Tuesday afternoon, FBI investigators were seen going in and out of a home in Green Township, and Greater Cincinnati Hazardous Materials crews were also on scene. Public records show that Gilb has lived at the home that was searched by the FBI since 2006.
Gilb is charged with one count of possession of an unregistered destructive device and one count of transport and receipt of explosive materials without a license or a permit.
"This alleged activity posed a serious risk to public safety," said Elena Iatarola, FBI Cincinnati Special Agent in Charge, in a press release. "The FBI worked closely with our law enforcement partners to neutralize this potential danger and protect the community."
According to federal court documents, Hamilton County Sheriff's Office deputies were dispatched to East Miami River Road in Cleves on April 12 after getting reports of a large explosion in the area.
Deputies who arrived to the area of the explosion "discovered a blast crater in a small, wooded area."
The FBI was called in to assist, and investigators found what appeared to be a threaded metal pipe, a rechargeable battery pack, a soil sample with a grey colored residue and other components of a battery. Later on that same day, authorities found "several additional items of evidence" that an improvised explosive had been detonated in the area, court documents say.
The second explosion happened on March 23 on Mustang Drive in Okeana, Ohio, according to court documents.
"These incidents have similar characteristics to the April 12, 2025 suspected IED incident in Cleves," reads the document.
At that scene, the Butler County Sheriff's Office and its Public Safety Bomb Technicians found debris "in a circular pattern in the front yard around a tree stump," which had what appeared to be powder burns on it, court documents say.
Investigators didn't find any electronic components at that scene, but they did find other evidence, including shattered pieces of white PVC piping and tape with charring and explosive residue on it.
The third explosion Gilb is accused of facilitating happened on March 28, behind Mustang Drive and near Race Lane in Okeana.
A witness told investigators they'd seen a white BMW sitting on the roadway, just past a bridge just before the explosion.
"The witness stopped and saw something smoking to the right side of the guardrail," reads the federal court documents. "A short time later a loud explosion was heard and the white BMW left the area near the bridge and was observed traveling in the direction of Okeana, Ohio."
Later that same day, BCSO deputies saw that same vehicle driving along Mustang Drive, before dropping someone off at the same home where an explosive was believed to have been set off on March 23. That vehicle was owned by Gilb, court documents say.
At the third explosion site, law enforcement found evidence of "what appeared to be a blast seat beside Race Lane, Okeana, Ohio near the guardrail," court documents say.
That blast seat was just 36 inches from the edge of the roadway, documents say. The blast seat itself was roughly 17 inches wide and 3 and a half inches deep, officials said. Nearby, investigators found foil, fragments of burned and discolored PVC pipe and tape.
"The crater also had a smell of burnt powder and grayish black residue was found inside," reads the document.
Gilb was identified by multiple witnesses as "a person involved in constructing explosives," including the devices discovered at all three explosion sites, federal documents say.
According to federal officials, Gilb could face up to 10 years in prison if he's convicted on both of the charges he faces.
