On 15 September 2025, Maine State Police and Biddeford Police Department investigated a report of potential threats made by an individual at a restaurant in Cornish, directed towards the University of New England (UNE) in Biddeford.  A 24-year-old suspect was detained, evaluated at a hospital, and later transported to jail. The state fire marshal's office and the Federal Bureau of Investigation responded to assist in the investigation.  During the investigation, agencies found bomb-making materials in the suspect’s residence.

On 12 September 2025, a suspicious device was found underneath a news media vehicle in Salt Lake City, Utah next to an occupied building.  Police and fire department bomb squads responded.  The investigation determined that an incendiary device had been ignited, but "failed to function." On 13 September 2025, the Federal Bureau of Investigation, Salt Lake City Police Bomb Squad, and Unified Fire Authority Arson/Bomb squad served a warrant on a suspected residence in Magna, Utah, evacuating neighborhood residents.

On 11 September 2025, the Indiana State Police executed a search warrant at a private residence on Indianola Avenue in Indianapolis, following a criminal incident that occurred on 21 August 2025, on I-495. During the search, law enforcement discovered four improvised explosive devices (IEDs), psilocybin mushrooms, and marijuana. The investigation revealed that the 19-year-old suspect had been manufacturing explosive devices at the residence. The Bomb Squad arrived at the scene and rendered it safe.

On 9 September 2025, 14 explosive devices of “varying capabilities” were discovered inside the safe of a residence in Millscreek Township by the Federal Bureau of Investigation and Pennsylvania State Police, prompting evacuations in the area.  One device was described as having a wiring system capable of remote detonation.  A 40-year-old suspect was arrested and charged with possessing weapons of mass destruction, risking catastrophe, and recklessly endangering another person.

On 6 September 2025 at approximately 1600 hours, the Fairbanks Police Department (FPD) received a report of a possible explosive device that was found in a bathroom at a grocery store on Airport Way in Fairbanks, prompting the store to be evacuated.  FPD officers and Fort Wainwright’s Explosive Ordnance Disposal team responded.  The device was identified as a “deactivated 81 mm mortar shell” and was safely removed for disposal.  A juvenile suspect was identified and will be charged with terroristic threatening.