New Jersey drone mystery: What to know and what can be done

Since mid-November, what are believed by many to be large aerial drones have been spotted at night throughout central and northern New Jersey, causing concern for residents who have been posting videos of the aircraft on their social media accounts and prompting increasing demands from local and state officials for answers.

Lawmakers from New York and New Jersey this week sent a letter to the heads of the FBI, Federal Aviation Administration (FAA) and the Department of Homeland Security (DHS), requesting that the agencies brief them on the issue.

"We write with urgent concern regarding the unmanned aerial system (UAS) activity that has affected communities across New York and New Jersey in recent days," the letter from New York Sens. Chuck Schumer and Kirsten Gillibrand and New Jersey Sens. Cory Booker and Andy Kim stated. They asked to be briefed "as soon as possible on how your agencies are working with federal and local law enforcement to identify and address the source of these incursions."

While lawmakers and citizens alike await answers, here's what to know about the purported drone sightings.

Who's operating the purported drones, and why?

According to a DHS handout, "it is unclear who is operating the drones," but "the State of New Jersey and its agencies are not involved in the operation of these reported drones." The statement noted that determining the operators is "an aspect of the ongoing federal investigation."

Similarly, the DHS said there is as yet no "specific details about the drones," such as their manufacturer or model, and that while "drones are generally required to have tracking capabilities … not all drones comply, and investigations are ongoing to identify the operators."

Can't drones be tracked?

Any drone in the U.S. weighing more than .55 pounds must be registered with the FAA and can be easily tracked with GPS technology. Nearly 800,000 drones are registered in the U.S., according to the FAA.

Furthermore, drones weighing more than .55 pounds are required by the FAA to adhere to Remote Identification (Remote ID) rules – essentially the equivalent of a “digital license plate,” broadcasting the drone’s location and altitude from takeoff to shutdown. This allows authorized personnel to monitor the device and ensure its complying with regulations and not violating any flight restrictions.

That said, it's possible to alter commercially available drones to be untraceable.

The drones seen over New Jersey have been reported to be significantly larger than the average commercially available drone and should be easily trackable. It remains unclear why federal officials haven't yet been able to give the public a clear understanding of the origin of the recent purported drone sightings across the Northeastern U.S.

Are the purported drones dangerous?

"At this time, according to the FBI, there are no known specific or credible threats related to these sightings," the DHS handout states.

During a press briefing Thursday, White House National Security Communications Advisor John Kirby echoed the DHS statement, and said there was "no evidence at this time that the reported drone sightings pose a national security or a public safety threat." He added that "upon review of available imagery, it appears that many of the reported sightings are actually manned aircraft that are being operated lawfully."

Could the drone sightings actually be something else?

It is possible that some people may be mistaking general aviation, commercial or military aircraft for drones. "Drone activity can sometimes be mistaken for general aviation aircraft, such as planes or smaller helicopters, due to several overlapping characteristics," according to the DHS, including "advanced capabilities that allow them to mimic the flight patterns of helicopters or small planes, such as hovering or making rapid directional changes."

During his briefing Thursday, Kirby also said that federal authorities and state and local law enforcement "have not been able to … corroborate any of the reported visual sightings. To the contrary, upon review of available imagery, it appears that many of the reported sightings are actually manned aircraft that are being operated lawfully."

Mine Hill, New Jersey Mayor Sam Morris called Kirby's claim "ridiculous," telling ABC News it was "really insulting to all the people here who are living through this."

"Come on out, Mr. Kirby. And let's go out one night about 9:30, 10:00," Morris said. "I'll go out behind my town hall. And you can count them with me all night."

Can someone shoot down, capture or disable a drone?

Drones generally can't be shot down or captured, for both legal and safety reasons, according to the DHS: "Shooting down a drone can pose safety risks to people and property on the ground. Debris from a downed drone can cause injury or damage, especially in populated areas.

Additionally, the small size and maneuverability of drones make them difficult targets, even if there should be a reason to shoot them down. And while "non-kinetic methods such as jamming or hacking can be used" to disable drones, "they require sophisticated technology and expertise," the DHS says.

It's also not a good idea to shoot them down yourself. Doing so in New Jersey, for example, is illegal and violates federal law, since drones are regulated by the FAA. According to the DHS, any person who shoots down a drone could be fined up to $250,000 and sentenced to up to 20 years in prison.

State and local authorities also have little to no say legally regarding drone activity, since drones are FAA regulated.

Can anyone legally operate a drone?

Yes and no. As already noted, any drone that weighs more that .55 pounds must be registered with the FAA to be operated legally in the U.S. If a drone weighs more than .55 pounds, it's no longer classified as a small unmanned aircraft and the operator must obtain a special petition exemption approval from the FAA to fly it.

Further, commercial drone operators must become FAA certified by passing a knowledge test.

Both commercial and recreational operators must keep their drone within their line of sight at all times, or have an observer who can see the drone and is in direct communication with the operator. Operators also cannot operate drones at night unless they have anti-collision lighting and are FAA-certified to do so.

Can drones fly anywhere the operator wishes?

No, they can't – not legally, at least. Recreational drones must fly at or below 400 feet, and all drones must avoid prohibited or restricted airspace – such as airports, critical national infrastructure, and even major sporting events – unless the operator secures special permission to fly in restricted airspace.

Even if a drone operator wanted to fly in certain restricted airspaces, most commercially available drones include technology that recognizes geofencing, which is a virtual boundary around designated restricted areas that will not allow a drone to fly in that airspace, even if the operator attempts to do so.

What should you do if you see a drone?

The DHS recommends that anyone who sees what they consider to be suspicious drone activity should report it to their local police. If you live in New Jersey, you can also report it to the New Jersey Office of Homeland Security and Preparedness Counter-Threat Watch Unit at 866-4-SAFE-NJ (1-866-472-3365) or tips@njohsp.gov.

ABC News' Ayesha Ali, Clara McMichael, Sam Sweeney and Christopher Watson contributed to this report.