As the US military conducted air defence drills, the sound of a huge explosion was heard in the area surrounding Washington DC, according to reports.
The City of Annapolis Office of Emergency Management said an authorised Department of Defence flight caused the sound. It was heard just after 8pm local time and registered as a 'seismic-like event'.
As reported by the Mirror, residents in nearby Maryland and Virginia all reported hearing a large explosion - which sparked panic.
