Dozens of witnesses have reported seeing drones in New Jersey starting in November. At first, the drones were spotted flying along the scenic Raritan River, a waterway that feeds the Round Valley Reservoir, the state’s largest aquifer, about 50 miles west of New York City.

The U.S. government has no evidence that drone sightings reported in New Jersey pose a national security or a public safety threat, White House national security spokesperson John Kirby said on Thursday.