For over a week, New Jersey residents have spotted unidentified aircraft in the northern part of the state, including Morris County and near Newark — and now the authorities are urging people to remain calm.

The FBI’s Newark office, along with Morris County officials, recently issued a statement asking the public to share any information they might have on the mysterious drones, while reiterating that there is “no known threat” to the public. And NJ Governor Phil Murphy said that his office is actively monitoring the situation.

The drones were captured on camera by residents in multiple boroughs in the state, mostly at night. Some images and videos shared in news broadcasts and social media depict strange winged aircraft that look like small planes (or “car-sized drones”). Others seem like groups of consumer-level drone copters.

The drones would fly back and forth for “hours,” some witnesses said. Following the reports, the FAA has banned drones from flying over President-elect Donald Trump’s New Jersey golf course, NJ.com reports.