Police are investigating reports of reports of an "active shooter" at a defence company General Dynamics in Portsmouth, Virginia.
The call was received earlier in the day fro a security guard on site and Portsmouth police have called for people to stay clear of the area.
Police are currently searching the facility although there has been no confirmation of a weapon being found.
Officials said it is an active investigation and there was no further information at this time.
Workers at the facility were either being held outside the building, or inside rooms within the compound.
More than 80 per cent of the business has been searched so far.
A spokesperson for General Dynamics said that no shots had been fired.
