What hazard category would be if a truck explodes downtown near a government building?

If a truck explodes downtown near a government building, it would likely fall under the hazard category of a "terrorism incident" or "explosive hazard." This situation poses significant risks to public safety, infrastructure, and could lead to mass casualties. Additionally, it may trigger emergency response protocols due to the potential for damage and fear in the community. The incident would also be classified as an emergency management issue, requiring coordination between local law enforcement, fire departments, and emergency medical services.