Federal Directive 5240.01 brings in the military. From the directive:
Never mind the Posse Comitatus Act; the Biden/Harris regime has told the Pentagon it can kill US citizens on American soil.Defense Intelligence Components may provide personnel to assist a Federal department or agency, including a Federal law enforcement agency, or a State or local law enforcement agency when lives are in danger…
Assistance in responding with assets with potential for lethality, or any situation in which it is reasonably foreseeable that providing the requested assistance may involve the use of force that is likely to result in lethal force, including death or serious bodily injury. It also includes all support to civilian law enforcement officials in situations where a confrontation between civilian law enforcement and civilian individuals or groups is reasonably anticipated.