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.

Residents across New Jersey are continuing to report sightings of mysterious drones flying over their homes. Officials have downplayed the situation, however, and experts are offering some explanations for the activity.