Several weeks of mysterious drone swarms over the skies of one New Jersey county near the military research and manufacturing facility Picatinny Arsenal have sparked concerns among residents and prompted an FBI investigation.  

"It's kind of unsettling," Mike Walsh, a Morris County resident who has spotted the drones on numerous occasions, told local media outlet PIX11 News.

He said some drones "are very big, probably the size of a car." 

Since Nov. 18, Walsh and many other residents have spotted these drones in the night sky. 

"They're kind of go slow," he said, adding, "They come towards you. Then they change direction a little. They're all going different ways."

We first detailed the story on Nov. 19 in a note titled "Spy Drones? "Unusual Activity" Reported Over Morris County, New Jersey, Near Military Research Facility." 

The potential national security threat piqued our interest, considering multiple reports that the mysterious drones were observed near Picatinny Arsenal.

PIX11 News said the FBI's Newark field office has joined the investigation with other law enforcement agencies to determine who is flying these drones. 

PIX11 News contacted the FAA, which said it's received reports of activity near Morris County. The FAA has two Temporary Flight Restrictions prohibiting drone flights over Picatinny Arsenal and Trump National Golf Club Bedminster. 

"People think they were UFOs or being spied on," Erica Campbell told media outlet NBC 4 New York.

Given the close proximity to the highly controlled airspace around NYC, we suspect that if these drones actually posed national security threats, stealth fighter jets armed with Sidewinders would have neutralized these threats almost immediately.