Most chemical incidents are unintentional, such as accidental spills and leaks from storage vessels, transportation accidents, manufacturing process errors, and equipment malfunctions. In situations where the chemical incident is suspected to be the result of an act of terrorism, the Federal Bureau of Investigation (FBI) leads on-scene coordination, as well as the appropriate federal law enforcement response, including intelligence collection operational activities, and criminal investigations For chemical incidents involving other forms of deliberate criminal activity, the FBI may lead or support SLTT on-scene coordination and law enforcement activities; depending on the nature of the incident, capabilities of SLTT authorities, and triggering of relevant Federal authorities. Law enforcement and investigative operations at the national level are coordinated by the FBI-led Weapons of Mass Destruction Strategic Group (WMDSG), an interagency crisis action team. The WMDSG includes a FEMA-led Consequence Management Coordination Unit (CMCU) which ensures information is shared and coordinated across the Response, Protection, Prevention, Mitigation, and Recovery mission areas.
![Figure 79: FBI Weapons of Mass Destruction (WMD) training, Seattle 2015](/sites/default/files/photos/fema_kpf-chem_figure-79.jpg)