For weeks, New Jersey residents have spotted mysterious drones in the night sky throughout the state. Some New Yorkers and Pennsylvanians have seen them, too. These sightings have confounded local and federal authorities, who have been unable to determine the drones’ origins or their purpose. Here’s what we know about the ongoing mystery.

US officials have stressed that the strange drone sightings above New Jersey in recent weeks don't appear to be the work of a foreign adversary.